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PuULthad/'h^  Ric/toprlson-  &Lord-. 


> 


\ 


ADDITIONS 


TO  THE 


OE 


XAVIER  BICHAT. 


BY  P.  A.  BECLARD, 

PnOFESSOn  op  ANATOMT  and  PUTSIOIOGT  to  the  PACtTLTT  OF  MEDICINE 
OF  PARIS,  &C. 


Crati0lateD  from  tfie  jTrencf)* 


BY  GEORGE  HAYWARD,  M.  D. 

FEItOW  OF  THE  AMERICAN  ACADEME  OF  ARTS  AND  SCIENCES, 
AND  OF  THE  MASSACHUSETTS  MEDICAE  SOCIETT. 


BOSTOJ^T: 

PUBLISHED  BY  RICHARDSON  AND  LORD. 

T.  H.  A.  FROST,  PRINTER. 

1823. 


Bec-3v\-; 


DISTRICT  OF  MASSACHUSETTS,  to  wit  : 

District  Clerk's  Office. 

BK  IT  REMEMBERED,  That  on  the  eijjhth  day  of  January,  A.  D.  1823,  in  the 
forty-seventh  year  of  the  Independence  of  the  United  States  of  America,  Richardson  Sr 
Lord,  of  the  said  District,  have  deposited  in  this  office  the  title  of  a book,  the  right  whereof 
they  claim  as  proprietors,  in  the  words  following,  to  -wit : 

“ Additions  to  the  General  Anatomy  of  Xavier  Bichat.  By  P.  A.  Bedard,  Professor  of 
Anatomy  and  Physiology  to  the  Faculty  of  Medicine  of  Paris,  &c.  Translated  from  the 
French.  By  George  Hayward,  M.  D.  Fellow  of  the  American  Academy  of  Arts  and 
Sciences,  and  of  the  Massachusetts  Medical  Society.” 

In  conformity  to  the  Act  of  the  Congress  of  the  United  States,  entitled,  “An  Act  for  the 
encouragementof  Learning,  by  securing  the  copies  of  Maps,  Charts  and  Books  to  the  Au- 
thors and  Proprietors  of  such  Copies,  during  the  times  therein  mentioned  and  also  to  an 
Act  entitled,  “ An  Act  supplementary  to  an  Act,  entitled  An  Act  for  the  encouragement  of 
Learning,  by  securing  the  Copies  of  Maps,  Charts  and  Books,  to  the  Authors  and  Proprie- 
torsof  such  Copies  during  the  times  therein  mentioned  ; and  extending  the  benefits  thereof 
to  the  Arts  of  Designing,  Engraving  and  Etching  Historical  and  other  Prints.” 

/ JOHN  W.  DAVIS, 

Clerk  of  the  District  of  Massachusetts, 


NOTICE 


BY  THE  EDITOKS  OF  BICHAt’s  GENERAL  ANATOMY.* 


WE  announced  in  1818  an  edition  of  Bichat’s  General 
Anatomy,  to  which  Messrs.  Pinel,  Bedard  and  Laennec, 
were  to  contribute,  and  we  engaged  to  give  with  it  as 
faithful  a portrait  as  possible  of  its  illustrious  author ; 
being  editors  of  the  works  of  Bichat,  connected  with  him 
for  many  years  in  daily  relations  and  constantly  honoured 
with  testimonials  of  his  esteem  and  friendship,  we  owed 
this  respect  to  his  memory ; but  unfoi’eseen  circumstances 
have  prevented  the  execution  of  this  design  by  depriving 
us  of  the  co-operation  of  Messrs.  Pinel  and  Laennec. 

M.  Pinel  is  compelled  to  devote  to  the  care  of  his 
health  the  few  moments  that  are  left  by  his  private  duties  ; 
and  it  is  to  his  son,  the  worthy  inheritor  of  a name  which 
will  form  an  epoch  in  the  history  of  medicine,  that  we 
are  indebted  for  the  notice  placed  at  the  commencement 
of  this  volume. 

* These  Additions  of  Professor  Bedard  were  incorporated  into  an 
edition  of  Bichat’s  General  Anatomy,  which  was  published  in  Paris  in 
1821 ; many  copies  however  were  issued  in  a separate  form  for  the  beneht 
of  those  who  previously  owned  the  works  of  Bichat. — Tk. 


IV 


NOTICE 


M.  Laeniiec,  after  a severe  disease,  has  been  compelled 
to  leave  the  capital,  at  a moment  when  he  would  have 
desired  to  liave  demonstrated  all  that  can  be  drawn  from 
the  new  mode  of  investigation  which  he  has  made  known. 

It  is  then  to  Professor  Bedard  alone  that  we  are  in- 
debted for  this  volume  of  Additions  which  recent  works 
rendered  necessary  and  which  will  make  complete  the 
General  Anatomy. 

M.  Bedard  has  laid  under  contribution  not  only  the 
writings  of  the  French  anatomists  and  physiologists,  but 
also  all  the  important  works  published  in  Germany  and 
England,  the  Treatises  of  General  Anatomy  of  J.  F. 
Meckel,  J.  Gordon,  the  Prodromus  of  the  great  Anatomy 
of  Mascagni,  the  Flystology  (description  of  the  textures) 
of  Meyer,  the  Table  of  General  Anatomy  of  Bock,  and 
every  thing  which  has  appeared  upon  each  texture  in  par- 
ticular. He  has  thought  proper  to  add  to  the  history  ol 
each  system  an  article  upon  its  morbid  states,  and  to  de- 
vote a particular  chapter  to  the  preternatural  textures. 
Most  of  the  facts  relative  to  morbid  anatomy  have  been 
derived  from  the  general  treatises  of  Morgagni,  Voigtel, 
Baillie,  Otto,  Cruveilhier,  and  a great  number  of  particu- 
lar treatises,  among  others  the  excellent  work  of  M.  Laen- 
nec,  who  has  cultivated  this  science  with  so  much  success. 

M.  Bedard  has  added,  to  the  interesting  observations 
which  his  researches  have  furnished  him,  many  which 
arc  peculiar  to  him,  upon  the  anatomy  of  man  in  health 
and  upon  the  various  alterations  of  the  textures. 

M.  Bouvier,  avIio  is  ranked,  from  having  gained  eight 
prizes  from  the  Faculty,  among  the  number  of  its  most 


BY  .THE  EDITORS. 


V 


distinguished  pupils,  has  assisted  Professor  Bedard  in  his 
labour,  who  is  pleased  to  render  justice  to  his  zeal  and 
his  information. 

All  the  portraits  of  Bichat,  both  engravings  on  copper 
and  lithographic  drawings,  are  far  from  being  resem- 
blances. The  medals  of  the  Medical  Society  of  Emula- 
tion and  the  busts  even  hardly  recall  any  of  his  features. 
We  find  them  rather  in  the  picture  of  his  last  moments, 
exhibited  at  the  Saloon  in  1818.  M.  Petroz,  who  pos- 
sesses it,  has  allowed  us  to  consult  it,  and  has  entrusted 
to  us  the  mask  in  plaster  moulded  upon  the  face  of  Bichat 
some  hours  after  his  death.  It  is  by  the  aid  of  this  piece, 
and  the  advice  of  all  those  who,  like  ourselves,  have 
known  him  very  particularly,  that  we  have  succeeded 
beyond  our  hopes,  since  the  portrait  that  we  have  had 
engraved  for  this  edition,  when  viewed  by  those  whom 
Bichat  honoured  with  his  friendship,  has  recalled  im- 
mediately to  their  minds  the  great  man  whose  remem- 
brance is  so  dear  to  them. 


4. 


•t 


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'.  ■'■;■■■  ’.1'‘'  ,,  '^4';-',i'.  A,'  :■  '.  ■' ' ' ‘ 

;■  >' , >,’.':'M^«.  ; ■ i'V..;  ■ ' , iii;/,»|((*,,,i;A^^^  ,'  . ’ /-J 

,i 

j 


HISTORICAL  NOTICE 


OF 

XAVIER  BICHAT. 


IT  is  easy  to  enumerate  men,  who,  in  the  sciences, 
have  thought  for  themselves ; their  genius  opens  the  path 
of  discovery  and  the  multitude  follows  them.  Bichat 
enjoyed  this  happy  privilege.  Anatomy  and  physiology 
will  always  consider  him  among  the  number  of  those 
Avhose  works  are  the  most  fruitful  in  useful  results,  and 
history  will  assign  him  one  of  the  first  places  in  that 
brilliant  epoch  of  medicine  which  gave  so  great  an  eclat 
to  the  end  of  the  eighteenth  century. 

Xavier  Bichat,  born  at  Thoirette,  in  the  department 
of  Ain,  on  the  11th  of  November,  1771,  pursued  his 
classical  studies  at  Lyons,  and  distinguished  himself 
especially  in  rhetoric  and  philosophy.  He  commenced, 
in  that  city  the  study  of  anatomy  and  surgery  under  Marc- 
Antoine  Petit.  The  political  troubles  of  1703  having 
soon  obliged  him  to  remove  from  that  unfortunate  city, 
he  came  to  Paris  with  the  intention  of  perfecting  himself 


vm 


HISTORICAL  NOTICE. 


at  the  school  of  Desault,  that  he  might  afterwards  practise 
surgery  in  the  armies.  But  soon  a more  brilliant  and 
extended  path  opened  before  him.  Having  one  day  writ- 
ten down  a clinical  lecture  of  Desault,  in  the  absence  of 
the  person  whose  duty  it  was,  the  reading  of  it  occasioned 
the  greatest  sensation.  The  master  knew  henceforth  how 
to  appreciate  the  merit  of  the  pupil.  He  offered  to  him 
his  house,  treated  him  as  a son  and  associated  him  with 
his  glory  and  his  labours. 

Endowed  with  an  indefatigable  ardour,  Bichat  did  not 
disappoint  the  exalted  hopes  of  his  benefactor.  The 
variety  of  his  occupations  was  his  only  relaxation,  and  his 
methodical  mind  and  wonderful  facility  made  him  acquire 
with  ease  all  the  knowledge  which  is  ordinarily  the  fruit 
of  long  and  painful  study. 

, Bichat  was  scarcely  twenty  three  years  of  age  when 
Desault  died,  (in  1795)  and  so  far  from  being  overwhelm- 
ed bji-  this  unforeseen  loss,  it  appeared  to  redouble  his 
activity.  The  dressings  at  the  Hotel-Dieu,  the  daily  visits 
to  the  patients,  consultations,  dissections,  and  operations 
on  the  dead  body,  had  heretofore  employed  all  his  time  ; 
the  death  of  Desault  created  for  him  new  occupations ; 
gratitude  made  it  his  duty  to  publish  the  researches  and 
labours  of  the  master  who  had  adopted  him.  He  wished 
also  then  to  commence  his  career  as  a teacher. 

In  the  winter  of  1797  he  gave  his  first  course  of  anato- 
my, and  his  second  the  year  following.  After  his  duty 
at  the  Hotel-Dieu  was  finished,  he  superintended  the  dis- 
sections of  more  than  eighty  pupils ; he  performed  nu- 
merous physiological  experiments  upon  living  animals: 


HISTORICAL  NOTICE. 


IX 


prepared  for  the  press  the  surgical  works  of  Desault,  and 
composed  memoirs  for  the  Medical  Society  of  Emulation, 
of  which  he  was  one  of  the  founders. 

It  was  at  this  period  that  a revolution  took  place  which 
was  to  change  the  face  of  the  science.  Professor  Pinel 
was  the  first  to  perceive  that  a disease  can  only  be  an 
alteration  of  textures  or  of  organs  ; that  it  is  necessary  to 
study  these  organs  and  textures,  first  under  the  relation 
of  their  structure  and  then  under  that  of  their  functions, 
before  we  can  arrive  with  certainty  at  a knowledge  of 
their  alterations ; and  that  thus  analysis  in  medicine  con- 
sists in  referring  the  symptoms,  the  external  signs  of  dis- 
eases, to  the  suffering  and  morbid  alteration  of  some 
organs ; to  study  them  in  their  seat,  is  to  derive  from  the 
knowledge  of  this  seat  the  indications  of  the  treatment, 
and  finally  to  class  them  according  -to  the  analogy  or  the 
difference  of  the  affected  textures.  Such  was  the  original 
idea,  which  presiding  over  the  execution  of  the  Noso- 
graphic  PA^7o^OjoA^5'Me,  published  in  1798,  had  just  over- 
thrown forever  that  badly  constructed  scaffolding  raised 
upon  the  incoherent  plans  of  the  chemical,  humoral  and 
mathematical  physicians,  and  which  would  lay  the  first 
foundations  of  a true  physical  science. 

Bichat,  struck  with  the  description  and  the  distinction 
of  the  mucous  and  serous  membranes,  and  especially  with 
the  classification  of  their  disease;s,  seized  this  first  idea, 
made  new  researches,  and  extended  them  to  all  the  mem- 
branes of  the  body ; and  in  eighteen  months  after  (in  1800) 
he  published  his  Treatise  upon  the  Membranes,  a model 
of  precision,  originality  and  Sinalytical  method,  which  was 


2 


X 


HISTORICAL  NOTICE. 


afterwards  embraced  in  his  General  Anatomy,  enriched 
with  happy  developments  and  new  ornaments. 

It  was  a spectacle  worthy  the  regard  of  history,  that 
noble  emulation,  frank  and  generous  rivalship,  in  this 
period  of  enthusiasm  and  discovery,  should  turn  every 
thing  to  the  advantage  of  science.  If  Bichat  owed  to 
Professor  Pinel  the  idea  of  his  work,  the  latter  in  his  turn 
drew  new  lights  from  the  researches  of  the  young  anato- 
mist, and  corrected  in  the  second  edition  of  his  Noso- 
graphy  the  classification  of  the  diseases  of  the  fibrous, 
synovial  and  cellular  systems.  This  alliance  of  nosogra- 
phy  with  anatomy  and  physiology,  this  mutual  exchange 
of  instruction,  formed  one  of  the  characteristic  traits  of 
this  period. 

Physiology  is  the  inseparable  companion  of  anatomy ; 
the  structure  of  the  organs  is  only  interesting  as  it  leads 
to  researches  with  regard  to  their  functions ; thus  the 
Treatise  upon  Life  and  Death  followed  soon  after  the  first 
works  of  Bichat  upon  Anatomy  ; it  appeared  the  same 
year.  It  is  in  this  work  that  he  began  to  develop  that 
distinction  of  the  two  lives,  the  organic  and  animal,  which 
he  has  reproduced  under  a thousand  forms,  but  which 
cannot  be  admitted,  as  has  been  proved  by  Legallois, 
without  some  limitations.  The  richness  of  the  means 
with  which  he  pursued  the  development  of  this  idea  can- 
not be  too  much  admired.  The  beautiful  experiments 
that  fill  his  Treatise,  the  facts  that  are  made  known  by 
them  and  the  bold  and  profound  thoughts  that  shine  in  a 
great  number  of  passages,  are  more  than  sufficient  to  make 
us  excuse  some  flights  of  a vivid  and  ardent  imagination. 


HISTORICAL  NOTICE. 


Bichat,  in  his  two  first  works,  had  only  thought  of 
anatomy  and  physiology ; but  the  circle  of  his  ideas  en- 
larging as  he  reflected  on  his  subject,  he  ventured  to  leave 
the  beaten  track,  and  published  in  the  following  year  his. 
General  Anatomy,  which  placed  the  seal  upon  his  repu- 
tation, and  which  was  translated  into  almost  every  lan- 
guage. Before  his  time,  anatomy  had  been  confined  to 
the  simple  description  of  the  organs  ; he  was  the  first 
who  thought  himself  able  to  rise  to  bolder  views.  He 
observed  that  the  human  body  exhibits  uniform,  identical 
systems,  subjected  to  the  same  laws  of  growth,  nutrition 
and  diseases  ; that  these  systems,  everywhere  present, 
can  be  studied  in  their  structure  as  in  their  functions,  so 
as  to  embrace  the  most  general  results  of  their  organiza- 
tion, and  the  most  fruitful  and  useful  applications.  From 
that  period  he  created  a new  science.  General  Anatomy. 
He  created  for  anatomy  and  physiology,  a species  of  phi- 
losophy, to  which  there  was  nothing  wanting  to  render  it 
perfect,  but  that  it  should  not  be  limited  to  the  study  of 
the  textures  of  man.  He  should  have  extended  his  views 
to  all  classes  of  animals,  traced  in  them  the  inferiority  of 
the  textures  and  organs,  and  observed  the  properties 
which  they  bore  or  the  new  functions  to  which  they  are 
called.  Comparative  anatomy  and  physiology  would  have 
furnished  to  his  lively  and  brilliant  imagination  the  most 
novel  views,  the  most  substantial  knowledge,  and  the 
most  ingenious  analogies. 

It  is  astonishing  that  Bichat  with  that  independence 
of  opinion  which  characterized  him,  should  have  so  often 
brought  forward,  in  his  General  Anatomy,  those  old  ideas, 


xii 


HISTORICAL  NOTICE. 


Avhich  for  two  thousand  years  have  continued  in  the 
schools,  those  words  vital  force  and  vital  properties, 
abstractions  which  he  seems  to  have  taken  for  realities,  to 
which  he  gav^e  a separate  existence,  and  which  he  made 
perform  so  important  a part  in  the  animal  economy.  Yet 
for  a long  time  past  we  have  only  recognized  and  we  ought 
to  recognize  but  two  things  in  organization,  structure  and 
functions  of  organ.  The  philosopher  should  confine  him- 
self to  the  study  and  observation  of  the  sensible  phenom- 
ena which  matter  exhibits  in  these  two  states,  without 
endeavouring  to  penetrate  further  ; beyond,  an  immense 
abyss  commences  ; we  should  take  care  lest  we  fall  into  it. 

The  General  Anatomy  contains  also  the  first  germs  of 
a science  to  which  Bichat  would  no  doubt  have  devoted 
his  whole  life,  I refer  to  morbid  anatomy.  It  was  a 
natural  consequence  of  his  first  labours ; after  having 
studied  the  structure  and  functions  of  the  organs,  and  per- 
formed upon  living  animals  experiments  for  the  exact 
observation  of  their  phenomena,  either  in  a state  of  health 
or  in  that  of  disease,  he  was  naturally  led  to  seek  for  a 
knowledge  of  the  changes  in  their  texture  which  this  last 
state  brings. 

Appointed,  at  the  age  of  twenty-nine,  physician  to  the 
Hotel  Dieu,  he  devoted  himself  to  this  kind  of  research 
with  all  the  activity  that  was  natural  to  him  ; in  one  single 
winter  he  opened  more  than  six  hundred  bodies,  and  soon 
after  he  stated  in  a course  of  lectures  his  observations  upon 
the  morbid  state  of  the  organs.  It  was  in  this  course  that 
he  demonstrated  that  each  texture  has  a peculiar  mode  of 
disease  as  it  has  a peculiar  character  of  vitality ; that  even 


HISTORICAL  NOTICE. 


XUl 


in  the  intestines,  tiie  morbid  state  of  a membrane  can 
connect  itself  with  the  sound  state  of  the  neighbouring 
membranes,  and  that  it  is  very  important  to  know  how 
to  distinguish,  by  a correct  analysis,  the  peculiar  suffering 
of  these  different  textures,  Bichat  began  to  unite  into  a 
body  of  doctrine  the  fragments  of  morbid  anatomy  scat- 
tered throughout  his  works ; he  would  have  raised  to  the 
science  a monument  worthy  of  it  and  of  the  great  epoch 
which  owed  to  his  labours  a part  of  its  distinction.  But 
he  died  during  the  printing  of  his  Treatise  on  Descrip- 
tive Anatomy,  the  two  first  volumes  of  which  he  pub- 
lished himself,  (in  1801  and  1802)  and  left  the  third  im- 
perfect. 

One  day,  after  having  visited  some  specimens  of  morbid 
anatomy  subjected  to  maceration  and  having  been  exposed 
without  any  precaution  to  their  noxious  exhalations,  he 
fell  in  descending  a staircase  of  the  Hotel-Dieu,  and  the 
slight  shock  occasioned  by  this  fall  deprived  him  of  his 
senses.  A violent  affection  of  the  head,  very  severe  gas- 
tric symptoms,  a continual  tendency  to  stupor  and  ataxic 
phenomena  succeeded  with  rapidity,  and  Bichat  sunk  on 
the  fourteenth  day  of  his  disease,  22d  of  July,  1802. 

Thus  were  turned  to  bitter  regrets  the  hopes  that  he  was 
just  realizing ; thus  was  arrested  in  his  rapid  flight  this 
genius  who  seemed  to  hover  over  the  whole  edifice  of 
medical  science.  Bichat,  embracing  in  a single  view  all 
the  knowledge  connected  with  medicine,  saw  on  the  one 
hand  anatomy  brought  to  the  greatest  degree  of  exactness, 
physiology  established  for  the  first  time  upon  facts,  and 
the  description  of  diseases  reduced  to  simple  and  clear 


HISTORICAL  NOTICE. 


siv 

language  ; and  on  the  other,  morbid  anatomy  still  separ- 
ated from  physiology,  and  therapeutics  still  abandoned  to 
empiricism.  He  had  conceived  the  project  of  connecting 
by  a regular  chain  all  the  parts  of  the  art  of  healing,  of 
raising  a complete  system  of  medicine  founded  upon 
anatomy,  upon  the  study  of  the  functions  in  the  state  of 
health  and  in  that  of  disease,  upon  the  distinction  of  the 
textures,  the  sympathy  which  connects  them  together,  the 
observation  of  the  local  and  the  general  effects  of  medi- 
cines, and  the  results  of  the  examination  of  dead  bodies. 
He  would  no  doubt  have  executed  this  plan,  vast  and 
methodical  as  it  is,  which,  notwithstanding  the  preten- 
sions of  some  physicians  of  our  time,  is  yet  but  a project. 

Such  is  in  fact  the  happy  influence  which  the  great  men 
who  appear  from  time  to  time  have  upon  their  age,  that 
from  their  labours  as  from  an  inexhaustible  source,  new 
sciences  seem  to  flow.  Those  who  have  nothing  to  say 
continually  repeat  what  has  been  said  ; but  before  the  man 
of  genius  the  field  of  discovery  seems  to  enlarge  from  day 
to  day.  How  many  researches  has  he  to  make  in  morbid 
anatomy,  a physical  science,  which  only  considers  the 
symptoms  of  diseases  as  the  signs  which  should  be  refer- 
red to  the  alteration  of  the  textures,  who  seeks  in  these 
textures  the  various  lesions  produced  by  the  difierent 
degrees  of  diseases,  and  who  only  endeavours  to  go  from 
the  alterations  to  the  symptoms ! How  little  advanced  is 
morbid  physiology,  the  knowledge  of  the  functions  of  the 
organs  by  the  different  modifications  which  the  alterations 
produce  in  these  functions,  which  will  alone  resolve  an 
infinity  of  enigmatical  problems  of  our  organization,  and 


HISTORICAL  NOTICE. 


XV 


especially  make  known  by  pathological  analysis  the  dif- 
ferent properties  of  the  nervous  system  ! How  much  has 
anatomical  chemistry  been  neglected  even  to  this  day, 
the  research  into  the  composition  of  the  textures,  which 
would  alone  be  able  to  establish  the  identity  or  the  differ- 
ence of  the  systems  and  the  apparatus  of  the  human  body  ! 
Pathological  chemistry,  the  investigation  of  the  chemical 
changes  produced  by  the  alterations  in  the  organs,  k it 
not  an  entirely  new  science,  upon  which  we  have  hardly 
thought,  and  which  will  perhaps  give  the  explanation  of 
many  phenomena,  whose  character  and  cause  we  are  un- 
able to  determine  by  other  means  ? 

How  many  researches  has  Bichat  opened  for  us  the 
way  ! What  an  immense  inheritance  has  he  left  us  to 
improve  ! The  mind  can  hardly  conceive  that  the  life  of 
one  man  was  sufficient  for  so  many  labours,  for  so  many 
discoveries,  either  made  or  pointed  out ; Bichat  died 
before  he  completed  his  thirty-second  year  ! 

SCIPIO  PINEL. 


■■■I'll.'  ■'■ 


• f 


■ . 


H: 

"‘V'  ’■  ■ •.  p ' 


/ 


GENERAL.  ANATAOMY. 


ADDITIONS 

TO  THE 

GENERAL  OBSERVATIONS. 


Anatomical  Elements. 

Page  49,  volume  1,  Bichat^ s General  Anatomy . — 
“ If  you  would  have  only  general  notions  of  anatomy, 
you  can  study  each  organ  as  a whole ; but  it  is  essential 
to  separate  the  textures,  if  you  have  a desire  to  analyze 
with  accuracy  its  intimate  structure.” 

Some  have  attempted  to  extend  too  far  this  analysis  of 
the  textures  ; and,  as  in  chemistry,  we  recognise  in  the 
organic  substances  the  immediate  principles  which  them- 
selves result  from  the  union  of  the  simple  elementary 
bodies,  such  as  oxygen,  hydrogen,  carbon  and  azote,  they 
have  sought  to  discover  what  are,  in  the  organization  of 
animals,  these  primitive  elements,  the  assemblage  of 
which,  variously  modified,  gives  rise  to  the  secondary 
textures,  to  the  organic  systems  of  Bichat. 

3 


1» 


ADDITIONS  TO  THE 


The  ancients  had  already  admitted  an  elementary  fibre, 
{Jibra  simplicissima)  composed  of  earthy  particles  united 
by  a species  of  gluten,  and  being  able  to  assume  two  forms, 
the  one  linear  and  the  other  lamellated.  This  fibre  was 
the  base  of  the  cellular  texture,  w'hich  they  regarded  as 
the  substratum  of  all  the  solids  of  the  human  body.  But 
this  elementary  fibre  has  never  been  seen,  and  moreover, 
there  are  textures  which  we  cannot  reduce  by  decompo- 
sition to  the  simple  cellular  substratum. 

An  opinion  more  conformable  to  nature  is  that  which 
recognizes  in  the  organization  three  distinct  elements, 
the  cellular,  nervous  and  muscular  fibre.  Very  striking 
differences  characterize  these  three  primitive  textures,  and 
do  not  permit  them  to  be  confounded.  1st.  In  relation 
to  the  form  ; the  cellular  fibre  is  composed  of  fine  laminae 
and  delicate  filaments,  white  and  extensible  ; the  nervous, 
of  a soft  substance  nearly  fluid,  contained  in  a cellular 
envelope  ; the  muscular,  of  round  filaments,  soft,  pulpy, 
greyish  or  red.  2d.  In  relation  to  the  chemical  nature  ; 
one  is  resolved  into  almost  pure  gelatine  when  it  is  treated 
with  boiling  w'ater  ; the  other  is  essentially  formed  by 
albumen  united  to  a fat  substance,  and  the  third  by  fibrin. 
3d.  In  relation  to  the  vital  properties  ; those  of  the  cel- 
lular fibre  are  obscure  and  are  confined  to  the  latent  sen- 
sibility and  the  invisible  contraction  know'n  under  the 
name  of  insensible  organic  contractility , whilst  the 
nervous  has,  besides  the  faculty  of  transmitting  the  im- 
pressions to  the  mind,  sensibility  properly  so  called  ; the 
muscular  on  the  contrary,  is  distinguished  by  the  irrita- 
bility which  it  possesses. 

All  the  organized  textures  have  for  their  base  one  of 
these  three  primitive  fibres,  or  result  from  the  union  of 
many  of  them  ; thus  the  cellular  element  is  found  in  most 
of  tlie  organic  systems ; it  constitutes  almost  alone  the 


GENERAL  OBSERVATIONS, 


19 


cellular  texture,  the  serous  membranes,  the  dermis  of  the 
skin  and  of  the  mucous  membranes,  tbe  parietes  of  the 
sanguiferous  and  lymphatic  vessels,  and  the  fibrous  or- 
gans ; thus  the  muscular  system  is  formed  by  the  assem- 
blage of  the  muscular  and  cellular  elements,  &c. 

This  division  of  the  primitive  textures,  pointed  out 
by  Haller  and  Blumenbach,  has  been  followed  by  most 
modern  anatomists.  Some  have  modified  it  by  adding 
to  them  a fourth  element,  the  fibrous  texture.  It  is  to 
this  new  fibre  that  M.  Chaussier  has  given  the  name  of 
albugineous  fibre.  The  characters  which  he  gives  to  it 
are  a white  colour,  shining  like  satin,  and  a considerable 
density ; boiling  water  converts  it  in  great  part  to  gela- 
tine ; it  is  but  slightly  extensible  and  very  resisting  ; its 
vital  properties  are  hardly  perceptible ; it  is  this  which- 
forms  the  fibrous  or  albugineous  membranes,  the  tendons, 
aponeuroses  and  ligaments.  These  characters  resemble 
very  much  those  of  the  cellular  fibre,  from  which  the  albu- 
ginea seems  to  differ  only  in  the  greater  approximation  of 
the  particles,  which  is  the  reason  of  the  greater  tenacity 
it  possesses.  We  can  even  refer  to  a modification  of  the 
cellular  fibre  the  elastic,  yellowish  texture,  which  consti- 
tutes the  middle  texture  of  the  arteries,  the  yellow  liga- 
ments of  the  vertebras,  tbe  posterior  cervical  ligament  of 
animals,  &c.  and  which  is  distinguished  by  its  colour  and 
its  elasticity  from  tbe  common  or  albugineous  fibrous  tex- 
ture of  M.  Cbaussier.  Nothing  proves  more  the  great 
affinity  which  naturally  approximates  the  cellular  fibre  and 
these  two  species  of  fibrous  textures,  than  the  facility  with 
which  they  are  transformed  into  cellular  texture,  when 
they  disappear  preternaturally. 

If  we  consider  the  organized  elements  under  another 
point  of  view,  we  see  that  it  is  possible  to  bring  by  the 
analytical  method  the  different  textures  of  the  animal 


20 


ADDITIONS  TO  THE 


economy  to  a certain  number  of  primitive  forms,  which 
are  inseparable  elements  of  all  organization.  This  obser- 
vation has  occasioned  many  classifications  of  forms  or 
elementary  textures.  The  first  and  most  simple  is  that 
which  admits  but  two  of  them;  1st,  the  fibrous  fiorm  ; 
2d,  the  lamellated  form,  a division  already  established 
by  the  ancients.  A greater  extent  in  length  characterizes 
the  fibre  ; the  lamina  has  dimensions  nearly  equal  in 
length  and  breadth,  but  little  thickness.  The  fibres  and 
the  laminae  can  by  their  interlacing  leave  between  them 
spaces  variously  formed,  called  cells.  The  fibrous  struc- 
ture predominates  ; it  is  evident  in  the  nerves,  the  mus- 
cles, the  bones,  and  the  fibrous  textures ; some  organs 
exhibit  at  the  same  time  a fibrous  and  lamellated  tex- 
ture. 

Others  recognise  a greater  number  of  elementary  forms 
and  add  to  the  two  preceding  ones  the  globular  and  the , 
granulated  form ; the  first  belongs  especially  to  the 
fluids  ; the  second  is  observed  in  the  glandular  texture. 
They  admit  besides  as  secondary  forms,  1st,  the  cellular; 
2d,  the  vascular  ; 3d,  the  solid,  as  that  of  the  cartilages, 
the  bones,  &c. 

Other  divisions  also  exist  which  appear  to  be  founded 
at  the  same  time  upon  the  forms  and  upon  the  nature  of 
the  textures.  It  is  thus  that  Walter  establishes,  1st,  a 
cellular  or  membranous  texture  ; 2d,  a vascular  or  fibrous 
one  ; 3d,  a nervous  one.  So  we  find  in  the  classification 
of  Dumas,  1st,  the  cellular  or  spongy  texture ; 2d,  the 
muscular  or  fibrous  texture  ; 3d,  the  mixed  or  parenchy- 
matous texture ; 4th,  the  lamellated  or  osseous  texture. 
These  divisions  are  by  no  means  preferable  ; they  are  in- 
sufficient if  they  represent  the  secondary  textures  or 
organic  systems,  and  too  multiplied  if  they  only  express 
the  primitive  elementary  forms. 


GENERAL  OBSEE.VATIONS. 


21 


Notwithstanding  the  delicacy  of  microscopic  researches 
and  the  deceptions  so  difficult  to  be  avoided  in  this  kind 
of  experiments,  the  labours  of  Hewson,  Prochaska,  Wen- 
zel and  other  observers,  have  served  for  the  basis  of  a 
theory  of  the  organized  elements  which  differs  considera- 
bly from  the  other  opinions  upon  this  subject,  and  which 
has  been  particularly  developed  latterly  by  J.  F.  Meckel. 

According  to  this  anatomist,  the  solids  and  the  fluids  of 
the  human  body  can  be  reduced,  in  the  last  analysis,  to 
tw'O  elementary  substances,  one  formed  by  globules,  the 
other  by  a coagulable  matter,  which,  either  alone  or  united 
to  the  first,  constitutes  the  living  solids,  if  it  be  in  a liquid 
state,  and  gives  origin  to  the  solid  textures,  if  it  be  in  a 
concrete  state. 

The  globules  exhibit,  in  their  appearance  and  even  in 
their  nature,  differences  which  are  especially  relative  to 
the  places  in  which  they  are  examined.  In  the  blood, 
they  appear  flat  and  composed  of  a central  part  which  is 
solid,  and  of  an  external  part  which  is  hollow  and  vesi- 
cular. Those  of  the  kidneys  are  smaller  than  those  of 
the  spleen ; the  globules  of  the  liver  are  still  more  deli- 
cate. The  globules  contained  in  the  substance  of  the 
nerves  exhibit  a less  size  than  those  of  the  blood ; it  is 
the  same  in  the  lymph,  the  milk  and  the  chyle.  Certain 
fluids,  as  the  urine,  do  not  contain  globules.  Many  solids 
are  entirely  destitute  of  them  ; such  are  the  cellular  tex- 
ture, the  fibrous  parts,  the  cartilages  and  the  bones.  They 
abound  on  the  contrary  in  the  blood,  the  nerves  and  the 
muscles.  They  form  the  essential  part  of  the  textures, 
the  colour  and  nature  of  which  they  determine. 

These  globules  appear  to  undergo  modifications  accord- 
ing to  age  ; but  direct  experiments  are  wanting  on  this 
point.  Hewson  says  he  has  found  in  birds  and  reptiles, 
the  globules  of  the  blood  of  a different  form  and  size  in 


22 


ADDITIONS  TO  THK 


the  embryo  and  the  adult  animal.  In  the  first  periods 
after  conception,  the  mucous  and  homogeneous  mass  which 
constitutes  the  embryo  does  not  contain  globules ; it  is 
not  till  a more  advanced  period  that  it  is  composed  of  two 
substances,  one  fluid  and  the  other  solid,  every  where 
immersed  in  the  first.  The  globules  are  then  very  appa- 
rent, more  distinct  than  they  will  be  afterwards  ; they  are 
seen  in  all  parts  of  the  embryo. 

These  two  elements,  the  globules  and  the  coagiilable 
fluid,  may  assume  the  form  of  fibres  or  laminae.  The 
lamellated  form  belongs  almost  exclusively  to  the  fluid 
matter.  The  fibres  may  be  formed  by  this  substance  only, 
as  we  see  in  the  bones,  the  tendons,  &c.  ; they  are  the 
effect  most  often  of  the  union  of  the  globules  and  the  con- 
crete fluid,  of  which  the  nervous  and  muscular  systems 
exhibit  examples. 

These  considerations  of  Meckel  upon  the  organization 
of  animals  have  some  relation  with  the  division  of  the 
organized  elements  established  by  Pfaff,  which  admits  as 
primitive  elements  fibres  and  cells,  themselves  formed  of 
a series  of  particles  or  globules.  They  differ  from  it  in 
this  that  we  find  in  it,  besides  the  solid  globules,  the  idea 
of  a concrete  fluid  substance,  analogous  to  that  which  the 
ancients  designated  by  the  name  of  gluten.  It  is  accord- 
ing to  Meckel  the  cellular  texture  which  represents  this 
substance  ; it  regards  in  fact  this  texture  as  a sort  of  con- 
crete fluid,  as  we  shall  see  in  the  article  on  the  cellular 
system. 

Classification  of  Morbid  t.dnatomy. 

Page  59. — “ This  course  (of  classing  the  alterations 
according  to  the  systeins  to  which  they  belong)  is  incon- 
testably the  most  natural,  though,  as  in  all  divisions  in 


GENERAL  OBSERVATIONS. 


23 


which  we  wish  to  subject  nature  to  our  views,  there  are 
many  cases  which  it  almost  excludes.” 

The  recent  progress  of  morbid  anatomy  has  occasioned 
new  classifications  which,  without  being  entirely  exempt 
from  the  inconvenience  of  constrained  approximations, 
nevertheless  contain  useful  divisions  founded  upon  natural 
relations  .established  between  the  various  organic  altera- 
tions. Bayle,  Laennec,  Cruveilhier,  J.  F.  Meckel,  &c. 
have  been  particularly  engaged  in  this  subject. 

1st.  Havins:  seen  that  the  alterations  of  texture  have 
nearly  the  same  characters,  whatever  may  be  the  tex- 
ture they  affect,  they  have  found  the  greatest  advantage 
in  uniting  them  into  one  and  the  same  class,  so  that 
they  avoid  the  numberless  repetitions  which  an  opposite 
method  produces  ; they  exhibit  at  the  same  time  and 
under  the  same  point  of  view,  analogous  objects,  and  no- 
thing is  more  proper,  as  we  know,  to  hasten  the  progress 
of  any  science. 

2d.  The  same  method  has  been  applied,  though  with 
less  success,  to  the  derangements  that  affect  only  the  ex- 
ternal forms.  It  is  scarcely  any  where  but  in  the  original 
defects  of  conformation  that  a methodical  order  can  be 
followed  or  that  it  is  attended  with  any  real  utility.  The 
preternatural  derangements  of  form  have  too  little  resem- 
blance, to  make  it  advantageous  to  approximate  them. 
Thus  it  has  been  proposed  to  preserve  here  the  anatomi- 
cal order  adopted  by  Bonet,  Morgagni  and  in  part  by 
Bichat,  till  the  science  shall  be  sufficiently  advanced  to 
substitute  another  for  it. 

They  have  followed  the  same  principles,  as  much  as 
possible  in  the  subdivisions.  The  most  natural  and 
numerous  is  that  of  the  transformations  or  organic  pro- 
ductions, which  the  class  of  the  alterations  of  texture  em- 


24 


ADDITIONS  TO  THE 


braces.  They  are  characterized  by  the  preternatural 
development  of  a new  texture  in  the  part  which  is  the 
seat  of  them.  They  are  divided,  according  as  this  texture 
has  some  analogy  in  the  economy  or  is  wholly  foreign  to 
it,  into  organic  transformations  properly  so  called,  and 
into  degenerations  or  preternatural  textures  which  only 
exist  in  a state  of  disease. 

J.  F.  Meckel  is  hitherto  the  only  one  who  has  made 
an  application  of  these  data  to  a complete  system  of 
morbid  anatomy.  The  following  is  the  order  which 
he  has  pursued  in  a very  extensive  treatise  that  he  has 
published  in  Germany  on  this  subject : 

He  admits  the  two  great  divisions  of  which  we  have 
spoken,  viz.  the  alterations  of  form  and  those  of  texture. 
Among  the  first  are  found  arranged,  1st,  the  original  de- 
fects of  conformation,  subdivided  according  as  they  af- 
fect the  number  or  nature  of  the  parts,  into  defects  of 
quantity  and  defects  of  quality  ; 2d,  acquired  derange- 
ments of  size,  situation,  configuration,  &c.  which  com- 
prehends luxations,  hernias,  solutions  of  continuity,  con- 
tractions, dilatations,  atrophies,  &c. 

The  alterations  of  texture  are  confined  to  two  principal 
heads.  Some  change  only  the  physical  properties  of  the 
affected  texture,  such  as  the  colour  and  density.  The 
others  completely  change  its  organization.  These  being 
often  the  product  of  inflammation,  this  affection  is  naturally 
placed  here.  The  manner  of  the  separation  of  the  injured 
organs  is  described  at  the  same  time.  Finally  come  the 
transformations  and  degenerations  properly  so  called. 
The  author  still  ranks  among  the  preternatural  produc- 
tions worms  and  concretions. 


GENERAL  OBSERVATIONS. 


25 


We  shall  adopt  the  following  order  in  the  exposition  of 
the  morbid  alterations  of  each  system. 

f Situation. 

I Size  ^ Hypertrophy. 

1st.  Alterations  ill  the  exter-.{  ' ^Atrophy, 

nal  forms  j Density. 

I_Con6guration. 

[’Inflammation. 

oj  Alt  t-  • An  J Mechanical  Lesion  j p 

2d.  Alterations  m the  or-.|  ^ foreign  Bodies. 

ganization  by  | Transformation. 

t_Degeneration. 

„ . , _ , ( Defects  of  conformation. 

3d.  Alterations  in  the  development  | preternatural  Development. 


• ^ . A-  -■  ? ' r ; 

• ,1.  ' ' 
f ^ ' » '.*  ■ ’,v , 

. p \'y)^ 



■ WV'  ' ')  ■ » ' V . . ■■'  ,<■  . ^ J-  ■. 

' .'  '•■'■?*' ■■  ■■■^.  0, 


'“*•■■  •’’••'■  ' ' '■  rt . ! "■>»  ■ 

‘o  ' /flr- ■■■f  ..••  ^ 

-AT  ,.  . 

*'.  .'V*.'i.  v.‘>  ' ■ : ■ , 

, ■ ■.■..  ‘ a , ■ 


ADDITIONS 


TO  THE 

CELLULAR  SYSTEM. 


Mipose  Texture.. 

Page  128. — “ We  shall  see  also,  that  the  fat  is  sepa- 
rated by  an  exhalation  analogous  to  that  of  all  the  other 
exhaled  fluids,  that  is  to  say,  hy  vessels  of  a particular 
order,  which  are  intermediate  between  the  extremities  of 
the  arteries  and  the  cellular  texture.  We  can  apply  to 
the  exhalants  of  fat,  what  will  be  said  upon  the  exhalant 
system  in  general.” 

The  fat  does  not  appear  to  he  simply  deposited  in  the 
small  spaces  of  the  cellular  texture  ; it  has  a texture  which 
is  peculiar  to  it  and  which  contains  the  oily  fluid  of  which 
it  is  formed.  The  existence  of  the  adipose  texture,  which 
was  imperfectly  known  to  Malpighi,  distinctly  pointed 
out  by  A.  de  Bergen  and  Morgagni,  has  been  particularly 
demonstrated  by  W.  Hunter.  It  has  been  described  in 
turns  under  the  names  of  cellular  texture,  by  calling  our 
cellular  texture  filamentous,  of  fatty  texture  or  pan- 
nicle,  of  adipose  membrane  or  network,  of  adipose 
tunics  or  vesicles,  &c. 


28 


ADDITIONS  TO  THE 


The  general  arrangement  of  the  adipose  texture  already 
exhibits  many  peculiarities  which  cannot  arise  from  the 
fat ; this  fluid  cannot  of  itself  have  a determinate  form, 
and  nothing  is  more  variable  than  the  external  confor- 
mation of  the  fatty  texture.  In  one  place  it  is  a mem- 
branous layer  more  or  less  thick,  analogous  to  that  which 
exists  under  the  skin,  in  which  it  constitutes  the  fatty 
pannicle.  In  another  it  is  in  irregular  masses,  such  as 
are  found  around  the  kidneys,  in  the  orbits  and  the  thick 
part  of  the  cheeks.  In  other  places  the  adipose  texture 
exhibits  the  appearance  of  pyriform  elongations,  pedicu- 
lated,  such  as  are  seen  in  the  appendices  of  the  omentum, 
around  the  arteries  v/hich  go  to  the  peritoneum,  in  the 
openings  of  the  umbilicus  and  the  infra-pubien  rings, 
&c. ; in  the  omentum  it  forms  flattened  ribbons  or  kinds 
of  network  which  follow  the  course  of  the  blood-vessels. 
Accumulated  in  some  parts,  it  appears  under  the  form  of 
tumours  more  or  less  large  and  prominent,  examples  of 
which  are  seen  in  the  eminences  upon  the  nates  of  Hotten- 
tot women,  in  those  on  the  backs  of  dromedaries,  camels, 
the  bos  urus,  and  the  tail  of  the  Barbary  sheep. 

The  adipose  texture,  considered  in  its  external  organi- 
zation, is  not  less  distinct  from  the  fat  which  it  contains. 
Whatever  may  be  the  different  forms  it  assumes,  its  struc- 
ture is  every  where  the  same.  It  is  divided  into  rounded 
bunches,  separated  from  each  other  by  grooves  more  or 
less  deep,  of  a form  irregularly  oval,  and  of  a diameter 
varying  from  a line  to  half  an  inch  ; their  size  differs  also 
according  to  the  degree  of  corpulency  and  according  to 
the  part  examined.  Each  of  them  is  composed  of  smaller 
particles,  which  are  easily  separated  by  dissection.  These 
are  spheroidal,  miliary,  compressed,  similar  in  form  to  the 
seeds  of  the  grape  or  still  more  to  the  vesicular  granula- 
tions which  constitute  the  inside  of  oranges,  and  other 


CELLULAR  SYSTEM. 


29 


fruits  of  the  family  of  hesperides  ; we  discover,  by  the 
aid  of  the  microscope  that  they  are  themselves  a collec- 
tion of  united  vesicles,  exhibiting  precisely  the  same  ap- 
pearance, except  as  to  size,  since  according  to  Monro, 
their  diameter  is  from  the  eight  hundredth  to  the  six 
hundredth  of  an  inch.  According  to  Wolff  these  vesicles 
may  have  a different  size  in  different  species  of  animals. 
They  do  not  appear  to  communicate  with  each  other ; 
their  parietes  are  delicate  and  transparent,  which  has 
made  Monro  and  Clopton-Havers  who  have  observed 
them  in  the  marrow  of  the  bones,  compare  them  to  col- 
lections of  small  pearls.  They  contain  the  fatty  fluid,  the 
yellowish  colour  of  which  is  visible. 

The  adipose  texture  is  provided  with  a vascular  appa- 
ratus, which  has  been  very  well  described  and  drawn  by 
Mascagni.  Arterial  and  venous  branches  are  lodged  in 
the  grooves  which  separate  the  fatty  particles ; their  divi- 
sions represent,  by  their  anastomoses,  capillary  networks 
which  run  along  the  interstices  of  the  small  masses  or 
particles  of  which  they  are  composed  ; each  of  these  par- 
ticles receives  a little  artery  and  a little  vein  which  form 
for  it  a sort  of  vascular  pedicle  ; the  microscopic  vesicles 
themselves  are  penetrated  by  the  most  delicate  ramifica- 
tions, which  follow  at  first  their  interstices,  form  for  them 
also  a kind  of  pedicle  and  finally  terminate  in  their 
parietes.  This  collection  of  vessels  and  agglomerated 
grains  has  some  resemblance  to  a bunch  of  grapes  sus- 
pended by  its  peduncle,  and  in  which  each  of  the  grains 
that  compose  it,  has  besides  its  own  pedicle.  This 
arrangement  is  easily  seen  upon  a portion  of  fat  taken 
from  an  injected  body,  or  still  better  from  a part  naturally 
infiltrated  with  blood. 

A very  delicate  cellular  texture  seems  to  exist  between 
the  vesicles  and  around  them  ; this  texture  becomes  more 


30 


ADDITIONS  TO  THE 


apparent  in  the  interstices  of  the  particles  visible  to  the 
naked  eye,  which  it  connects  together  ; the  little  bunches 
that  arise  from  them  are  united  by  a firmer  texture  almost 
fibrous  in  some  parts,  evidently  ligamentous  in  the  palms 
of  the  hands,  on  the  soles  of  the  feet,  &c. 

The  fatty  texture  no  doubt  contains  absorbent  vessels, 
but  we  are  ignorant  of  their  arrangement.  It  is  the  same 
with  regard  to  the  nerves.  Its  intimate  nature  appears 
to  resemble  very  much  that  of  the  cellular  texture.  It  is 
in  fact  a soft  substance,  whitish,  extensible,  contracting 
when  distension  is  removed,  appearing  under  the  form  of 
fine  and  semi-transparent  laminae  and  having  the  greatest 
analogy  with  the  lamellatcd  or  cellular  fibre.  If  the  fat, 
which  it  contains,  disappears  preternaturally,  the  vesicles 
flatten  and  are  confounded  with  the  surrounding  cellular 
texture,  without  leaving  any  trace  of  their  existence. 
Hunter  says,  nevertheless,  that  in  these  cases  the  cellular 
texture  differs  in  some  of  its  properties  from  that  which 
never  contained  adipose  vesicles,  and  he  attributes  these- 
differences  to  the  presence  of  the  empty  vesicles  which 
the  first  contains. 

It  would  be  wrong  to  conclude  from  the  resemblance 
that  is  found  between  the  fatty  and  cellular  textures  that 
they  are  precisely  the  same.  It  is  easy  to  point  out  the 
characters  which  distinguish  them.  1st.  The  adipose 
vesicles  are  shut  on  all  sides,  and  their  substance  is  not 
permeable  to  the  fluids  which  tend  to  penetrate  it,  very 
different  in  this  from  the  areolar  substance  of  the  lamel- 
lated  texture.  This  is  proved  by  many  facts.  Take  a 
piece  of  adipose  texture,  raise  its  temperature  gradually 
by  means  of  warm  water,  until  it  is  sufficient  to  melt  the 
fat  without  altering  the  structure  of  the  vesicles,  the  oily 
matter  will  remain  contained  in  them  without  flowing 
out.  Expose  a bunch  of  fat  to  the  heat  of  the  sun  suffi- 


CF.LLULAR  SYSTEM. 


31 


dent  to  raise  the  centigrade  thermometer  to  + 40  degrees, 
you  are  very  certain  that  at  such  a temperature  the  fat 
must  be  perfectly  fluid  ; yet  not  an  atom  of  it  will  flow 
out ; cut  some  of  the  vesicles,  and  the  oily  fluid  will 
immediately  appear.  We  obtain  also  the  same  result  by 
compressing  between  the  fingers  a fatty  mass  ; the  fat 
does  not  escape  unless  the  vesicles  are  ruptured.  In  the 
most  extensive  emphysemas,  in  the  greatest  serous  infil- 
trations, the  effused  fluids  never  penetrate  the  vesicles ; 
the  fat  remains  distinct  and  is  not  mixed  with  these 
fluids.  If  it  were  otherwise,  should  we  not  see  during 
life,  the  fat,  fluid  at  the  ordinary  temperature  of  the  body, 
constantly  descending  to  the  lowest  places,  as  takes  place 
with  the  serum  of  dropsical  patients,  yielding  to  external 
pressure  in  parts  which,  such  as  the  feet  and  the  nates, 
are  continually  subjected  to  it,  as  is  observed  also  in 
oedema  ? The  adipose  vesicles  do  not  form,  like  the 
cellular  texture,  one  continued  whole ; they  are  merely 
contiguous  to  each  other.  This  is  easily  demonstrated  by 
inspection.  It  is  also  seen  in  anasai’ca ; the  liquid,  which 
is  poured  in  the  cellular  texture  that  is  interposed  be- 
tween the  adipose  particles,  separates  them,  and  they  con- 
tinue insulated  in  the  serum  that  surrounds  them.  3d. 
There  is  another  character.  Wherever  cellular  texture 
is  found,  there  are  parts  always  destitute  of  the  fatty  tex- 
ture, even  in  the  fattest  subjects.  Does  not  this  fact  seem 
to  indicate,  that  there  must  be  a peculiar  organization  in 
the  cellular  texture,  that  fat  may  be  developed  in  it? 
4th.  Finally  their  uses  are  very  different ; those  of  the 
adipose  texture  only  relate  to  the  fat  that  is  constantly 
exhaled  in  the  interior  of  its  vesicles,  and  constantly 
taken  up  by  the  absorbent  vessels ; the  cellular  texture 
has  much  more  important  uses,  since  it  forms  a common 
link  which  unites  all  the  parts  at  the  same  time  that  it 


32 


ADDITIONS  TO  THE 


insulates  them,  and  serves  to  facilitate  their  motions  and 
to  maintain  the  harmony  of  their  functions. 

Chemical  Nature  of  the  Fat. 

Page  128. — “ I will  not  treat  of  the  chemical  nature 
of  fat.  This  would  lead  me  into  details  foreign  to  this 
work.  Besides,  I could  add  nothing  to  what  modern 
chemists  have  said  upon  this  subject.” 

The  recent  labours  of  M.  Chevreul  upon  the  fixed  oils 
and  the  dilferent species  of  fat,  have  given  results  too  satis- 
factory not  to  be  mentioned  here.  The  fat,  far  from  be- 
ing an  immediate  principle  of  animals,  as  has  for  a long 
time  been  thought,  is  composed  of  two  peculiar  principles, 
non-acid,  designated  from  their  consistence,  by  the  names 
of  stiarine  and  ela'ine. 

Stearine  exhibits  a solid  mass,  without  colour,  almost 
inodorous,  insipid,  soluble  in  alkohol  and  preserving  the 
solid  state  at  the  temperature  of  38  degrees  of  the  cen- 
tigrade thermometer.  Elaine  on  the  contrary,  is  fluid  at 
a temperature  of  17  or  IS  degrees  ; it  is  without  colour 
or  yellowish,  lighter  than  water  and  much  more  soluble  in 
alkohol  than  stearine.  It  is  by  taking  advantage  of  this 
last  property,  that  we  can  separate  these  two  principles. 
For  this  purpose  we  treat  a certain  quantity  of  fat  with 
boiling  alkohol  ; as  the  liquor  becomes  cold  the  stearine 
is  precipitated,  taking  with  it  a little  elaine  ; the  greater 
part  of  the  elaine  remains  in  solution  with  a little  stearine. 
The  action  of  cold  upon  fat,  and  the  continued  contact  of 
this  substance  with  paper  that  has  not  been  sized,  can  also 
serve  to  demonstrate  the  existence  of  its  immediate  mate- 
rials. In  the  first  case,  the  stearine  becomes  solid,  whilst 
the  elaine  preserves  its  fluidity ; in  the  second,  the 


CELLULAR  SYSTEM. 


33 


elai'ne  is  absorbed  by  the  paper  and  the  stearine  remains 
on  the  surface. 

The  proportion  of  the  principles  of  the  fat  is  not  the 
same  in  all  animals  nor  in  all  parts  of  the  same  animal, 
hence  all  the  varieties  of  consistence  which  that  of  man 
exhibits.  However,  as  stearine  is  not  more  solid,  even 
when  pure,  at  a degree  of  heat  equal  to  the  temperature 
of  the  body,  the  fat  ought  at  least  to  be  semi-fluid  during 
life,  and  this  is  in  fact  what  is  observed  in  surgical  opera- 
tions, during  which  there  often  flows  with  the  blood  some 
oily  drops  coming  from  the  cutaneous  adipose  vesicles. 

Besides  the  peculiar  acid,  (the  sebacic  acid)  which  is 
produced  during  the  distillation  of  fat,  there  are  two  others 
that  are  obtained  by  treating  it  properly  with  an  alkali 
or  some  metallic  oxyd  ; one  is  the  margaric  acid,  so 
called  from  its  pearl  colour,  the  other  the  oleic  acid. 
Soaps,  which  result  from  the  action  of  alkalies  upon  oils 
are  nothing  but  salts  formed  by  these  two  acids  and  the 
base  that  is  employed.  M.  Chevreul  thinks  that  some- 
thing analogous  takes  place  in  the  spontaneous  decomposi- 
tion of  muscular  flesh,  when  it  happens  without  the  con- 
tact of  the  air ; he  considers  the  fat  of  dead  bodies  which 
is  produced  in  this  way  as  a kind  of  soap,  which  is  the 
result  of  the  action  of  the  ammonia  coming  from  the  de- 
composition upon  the  fat  contained  in  the  muscle. 

Intimate  nature  of  the  Cellular  Texture. 

Page  131. — “All  these  vague  ideas  of  concrete  juices, 
of  inorganic  glue,  of  hardened  juice,  that  have  been  applied 
to  the  cellular  texture,  have  no  solid  foundation,  and  rest 
neither  upon  experiment  nor  observation,  and  ought  to  be 
banished  from  a science  in  which  imagination  is  nothing 
and  facts  every  thing.” 

5 


34 


ADDITIONS  TO  THE 


The  ancients  do  not  appear  to  have  been  acquainted 
with  the  cellular  texture,  at  least  they  do  not  mention  it 
in  their  writings.  It  is  without  cause  that  some  have 
pretended,  that  they  have  found  some  notions  of  it  in  a 
passage  of  Hippocrates,  in  which  the  question  is  respect- 
ing the  general  permeability  of  the  textures.  Adrien 
Spigel  is  one  of  the  first  who  have  spoken  of  it.  Vesalius 
and  others  made  it  known  successively  in  difierent  parts 
of  the  body.  It  is  only  since  Haller  and  Bergen  that  it 
has  been  considered  as  generally  distributed  to  all  the 
parts.  “ Bordeu  appears  to  be  the  first  who  compared  the 
cellular  texture  to  a sort  of  slaver  or  glue.  Quesnay  said 
that  it  rather  resembled  a fluid  matter  than  an  organized 
solid.  WollT  went  further  ; rejecting  all  idea  of  cells,  he 
regarded  the  cellular  texture  as  a homogeneous  substance, 
glutinous  and  without  evident  organization.  Blumenbach, 
Ern.  Plainer  and  J.  F.  Meckel,  have  adopted  this  opinion. 
This  last  has  made  the  cellular  texture  his  concrete  fluid 
element.  The  following  are  the  observations  and  facts 
upon  which  these  anatomists  rely. 

1st.  Inspection,  say  they,  does  not  discover  in  the  cel- 
lular system  the  fibres  or  layers  of  which  it  is  supposed  to 
be  formed.  Examine  it  under  the  skin,  between  the 
muscles,  around  the  arteries,  on  the  exterior  of  the  mem- 
branes, every  where  is  found  a substance  semi-fluid,  trans- 
parent, tenacious  and  without  any  appearance  of  fibrous 
or  lamellated  structure.  If  fibres  or  laminse  be  developed, 
it  is  owing  solely  to  the  means  of  investigation  that  are 
employed.  Thus  when  we  separate  from  each  other  two 
contiguous  organs,  which  are  united  by  cellular  texture, 
two  muscles,  two  fasciculi  of  the  same  muscle  or  two 
muscular  fibres  ; when  we  raise  this  texture  from  the  sur- 
face of  the  organs  it  covers,  it  yields  to  the  distension,  is 
elongated  and  presents  the  appearance  of  delicate  laminae, 


CELLULAR  SYSTEM. 


35 


which  are  changed  to  round  filaments  if  the  distension  be 
carried  further,  precisely  as  if  it  were  a piece  of  glue  or 
paste,  according  to  the  expression  of  Bordeu.  The  dis- 
tension having  ceased,  the  parts  approximate,  and  the  in- 
terposed cellular  layer  reappears  homogeneous  and  per- 
fectly continuous.  So  when  we  examine  the  cellular  tex- 
ture of  the  scrotum  by  stretching  it  to  a kind  of  membrane, 
it  is  evident  that  the  laminae  and  the  interlaced  filaments 
that  are  seen  are  the  product  of  distension,  and  this  ap- 
parent organization  is  not  observed  until  after  having  de- 
veloped it  artificially. 

2d.  These  pretended  cells  do  not  exist  either  in  the 
mucous  texture,  which  does  not  exhibit  openings  on  its 
surface,  as  it  would  if  there  were  these  little  cavities. 
When  cavities  are  found  there,  it  is  because  foreign  bodies 
raise  it  up  and  give  it  a vesicular  appearance.  When,  for 
example,  the  cellular  texture  is  drawn  in  different  direc- 
tions, it  often  happens  that  it  is  penetrated  with  air  in  its 
interior.  This  air  then  assumes  the  form  of  bladders,  as 
it  does  in  soap  suds.  But  if  we  press  upon  these  bladders, 
they  disappear  ; and,  if  we  afterwards  reproduce  them, 
they  may  be  very  different  from  the  first.  W e give  them 
very  various  forms,  increase  or  diminish  their  number, 
precisely  as  in  soap  suds.  Inflation  produces  also  in  the 
mucous  texture  a cellular  appearance,  which  is  explained 
in  the  same  way  by  its  state  of  softness  and  semi-fluidity. 
The  injected  air  penetrates  it  easily,  and  the  distension, 
which  it  occasions,  produces  that  appearance  of  fibres  and 
interlaced  laminae,  which  has  been  said  to  be  peculiar  to 
this  texture,  whilst  it  is  a form  which  it  possesses  but  for 
a moment.  It  is  the  same  with  regard  to  the  cells  ob- 
served after  congelation  ; they  are  interstices  preternat- 
urally  produced  by  the  presence  of  a fluid  diffused  in  the 
cellular  texture. 


36 


ADDITIONS  TO  THE 


3d.  Any  part  of  the  cellular  system  exhibits  by  turns, 
fibres,  laminae  or  cells,  according  to  tbe  process  employed 
to  develop  in  it  either  one  or  the  other  structure.  Dis- 
tension produces  laminae  or  fibres,  according  to  the  extent 
to  which  it  is  carried  ; inflation  produces  cells,  &c. 

4th.  The  cellular  texture  is  permeable  ; most  fluids, 
such  as  air,  water,  pus  and  urine  traverse  it  easily  and 
run  over  a great  extent  in  its  interior ; solid  bodies  even 
have  penetrated  it,  and  have  gone  longer  or  shorter  dis- 
tances. How  can  we  admit  that  bodies  thus  immersed  in 
the  mucous  texture  follow  precisely  the  direction  of  the 
cells  and  of  their  orifices  ? Is  it  not  rather  the  medium, 
and,  as  it  were,  viscid  consistence  of  this  texture  which 
permits  it  to  yield  to  the  effort  of  the  substances  which 
tend  to  penetrate  it,  and  accommodate  itself  at  the  same 
time  to  the  various  forms  which  they  imprint  upon  it  ? 

5th.  Finally,  they  add,  that  in  the  foetus  of  man  and  in 
the  lowest  classes  of  animals  it  is  impossible,  under  any 
circumstance,  to  discover  any  organization  in  the  cellular 
texture  ; a mucous  and  homogeneous  mass  only  is  found. 

It  is  for  anatomical  inspection  to  pronounce  upon  the 
validity  of  these  objections,  which  cannot  be  overthrown 
by  the  single  consideration  of  the  phenomena  of  vitality 
which  the  cellular  texture  exhibits  in  diseases.  Would  it 
be  the  first  example  of  a texture  endowed  with  life,  whose 
homogeneous  structure  did  not  allow  distinct  laminae  or 
fibres  to  be  seen  ? Is  it  not  so  with  the  cerebral  substance, 
the  cartilaginous  texture  and  the  serous  membranes  ? We 
do  not  seek  to  know  if  the  texture  peculiar  to  the  cellular 
system  be  the  seat  of  an  evident  vital  action  ; this  point 
would  not  be  contested,  but  only  if  we  should  admit  that 
it  has  a fibrous  or  lamellated  organization,  or  whether  this 
organization  is  developed,  except  under  certain  influences 
of  which  it  is  the  immediate  result.  What  is  certain  is, 


CELLULAR  SYSTEM. 


37 


that  it  appears  under  many  circumstances  as  if  it  were 
i-eally  spongy  or  cellular,  and  there  can  be  no  incon- 
venience in  regarding  it  as  such. 


MORBID  ANATOMY  OF  THE  CELLULAR  SYSTEM. 

I,  Mterations  in  the  external  forms. 

The  size  of  the  cellular  texture  can  be  increased  in 
consequence  of  a more  copious  exhalation  of  the  fluids  it 
contains.  This  is  what  happens  in  anasarca  and  in  obesity 
or  corpulency.  The  serum  accumulated  in  anasarca  resem- 
bles that  of  dropsies.  It  runs  moreover  freely  through 
the  cellular  texture,  and  collects  in  general  in  the  most 
depending  parts.  The  looseness  of  this  texture  in  some 
regions  disposes  it  also  to  infiltration.  In  old  oedemas,  the 
cellular  texture  sometimes  acquires  a very  great  thick- 
ness ; it  seems  as  if  there  were  made  an  exudation  of  a 
fluid  capable  of  concretion  which  increases  its  density  by 
adding  to  the  laminae  which  compose  it. 

Obesity  or  the  accumulation  of  fat  is  general  or  local ; 
the  first  has  been  examined'under  the  article  upon  the 
cellular  fat. 

Fatty  tumours,  which  constitute  the  second,  are  of  very 
various  forms  ; their  size  is  sometimes  very  considerable  ; 
frequently  they  are  provided  with  a pedicle  through  which 
the  vessels  enter.  A cellular  coat  invests  them  on  the 
exterior ; their  structure  is  that  of  the  adipose  texture. 
The  vesicles  appear  to  be  more  numerous  than  in  a state 
of  health,  for  Monro  has  observed  that  their  diameter  is 


3S 


ADDITIONS  TO  THE. 


the  same.  These  tumours  are  especially  developed  in 
parts  which  contain  much  fat ; hence  the  frequency  of 
wens  or  sub-cutaneous  fatty  tumours. 

Besides  the  fluids  naturally  contained  in  the  cellular 
texture,  air  can  also  accumulate  in  it,  which  constitutes 
emphysema.  This  last  is  more  or  less  extended.  It  is 
sometimes  developed  after  death,  in  apoplexy,  urinous 
effusions,  &c. 

An  inci’ease  of  size  and  density  at  the  same  time 
appears  to  constitute  the  disease  described  under  the  name 
of  hardening  of  the  cellular  texture.  There  is  only  found 
in  it  in  fact  a greater  thickness  and  consistence  of  this 
texture,  which  scarcely  yields  to  the  pressure  of  the 
finger ; there  is  usually  joined  with  it  a more  or  less 
considerable  serous  infiltration.  This  affection  is,  as  we 
know,  almost  exclusively  confined  to  new  born  infants. 
It  is  below  the  skin  that  it  most  commonly  appears ; it 
has  also  been  seen  in  the  inter-muscular  cellular  texture. 

The  elephantiasis  or  disease  of  Barbadoes  is  owing  to 
an  alteration  of  the  same  kind. 

II.  Mterations  in  the  organization. 

Inflammation  of  the  cellular  texture  is  very  frequent ; 
there  are  many  varieties  of  it,  particularly  according  to 
the  part  it  attacks. 

In  acute  inflammation,  in  phlegmon  properly  so  called, 
the  cellular  texture  is  of  a more  or  less  bright  red,  as  if 
infiltrated  with  blood  ; the  serum  disappears,  the  small 
spaces  being  obstructed  are  much  less  permeable  than  in 
the  natural  state ; they  are  afterwards  filled  with  a concrete 
albuminous  matter,  which  resembles  a kind  of  jelly.  The 
ulterior  phenomena  differ  according  to  the  mode  of  termi- 
nation. In  the  most  common  cases,  suppuration  takes 


CELLULAR  SYSTEM. 


39 


place,  the  pus  hollows  out  a cavity  which  is  continually 
enlarging,  and  an  abscess  is  formed  ; or  there  is  an  ab- 
sorption of  the  effused  albuminous  m.atter,  and  consequent 
resolution.  At  other  times  this  matter  seems  to  become 
organized  at  the  same  time  that  its  consistence  increases  ; 
it  is  insensibly  confounded  with  the  organ  which  furnishes 
it ; this  is  what  is  observed  in  the  termination  by  indura- 
tion. In  gangrene,  the  mortified  cellular  texture  produces 
soft  eschars,  of  a whitish  or  grayish  colour ; it  is  reduced 
to  a sort  of  putridity. 

Chronic  inflammation  especially  produces  induration,  as 
wm  see  in  old  ulcers.  We  frequently  find  as  its  conse- 
quence that  sort  of  brittleness  of  which  Bichat  speaks 
(page  142).  In  some  cases  the  inflammation  is  accompa- 
nied with  ulceration  and  destruction  of  the  cellular  tex- 
ture. 

The  cellular  texture,  when  simply  divided  by  a mechan- 
ical lesion,  unites  quickly,  if  the  divided  edges  be  in  con- 
tact ; this  is  what  takes  place  in  the  closing  of  abscesses, 
in  the  union  of  wounds  by  the  first  intention,  &c.  The 
adhesion  is  established  by  means  of  a coagulable  fluid 
which  is  effused,  becomes  concrete  and  organized,  so  as  to 
form  a new  texture  for  some  time  more  dense  than  the 
surrounding  cellular  texture,  with  which  it  finally  becomes 
confounded. 

The  cellular  texture,  laid  bare  by  a solution  of  con- 
tinuity w’ith  a loss  of  substance,  exhibits  all  the  phenom- 
ena described  in  the  formation  of  fleshy  granulations  and 
of  cicatrization.  Vanhoorn  has  seen  in  amputations  the 
fatty  cellular  texture  disappear  at  first  from  the  surface 
of  the  wound,  to  be  afterwards  replaced  by  a new  texture, 
more  dense  and  resisting  than  the  first. 

Foreign  bodies  introduced  into  the  cellular  texture  pro- 
duce there  a more  or  less  severe  inflammation  ; the  suppu- 


40 


ADDITIONS  TO  THE 


ration  which  results  from  it  brings  them  gradually  to  the 
exterior,  so  that  if  they  be  deeply  situated,  they  thus  go  a 
considerable  distance.  We  see  this  texture  then  approxi- 
mating, constantly  uniting  behind  the  foreign  body,  whilst 
it  suppurates  and  opens  before  it.  This  peculiar  course 
of  the  inflammation  has  given  it  the  name  of  the  expul- 
ftory  inflammation. 

In  some  cases  however,  foreign  bodies  remain  in  the 
cellular  texture  without  producing  any  inconvenience 
there  ; there  is  formed  around  them  a kind  of  membrane, 
a cyst,  which  keeps  the  neighbouring  parts  from  their 
contact ; this  is  what  takes  place  in  some  sanguineous 
effusions,  when  the  presence  of  the  coagulum  does  not 
occasion  the  formation  of  an  abscess.  The  sac,  which 
contains  the  blood  in  false  aneurisms,  is  produced  by  an 
analogous  mechanism. 

Besides  inanimate  bodies,  solid,  fluid  or  gaseous,  which 
preternaturally  enter  the  cellular  texture,  we  find  there 
real  animate  bodies,  worms.  The  cysticercus  cellulosce, 
the  filaria  medinensis  or  hair  snake  properly  called,  and 
the  larvae  of  the  oestrus  have  been  met  with  by  different 
observers,  not  only  below  the  skin,  but  in  the  inter- 
stices of  the  muscles,  in  the  substance  of  the  pia  mater, 
and  even  upon  the  bones. 

Various  natural  textures  of  the  economy  are  preter- 
naturally developed  in  the  cellular  system. 

Osseous  and  cartilaginous  transformations  and  produc- 
tions are  not  rare  in  it ; they  are  observed  particularly 
in  the  cellular  texture  which  exists  in  the  neighbourhood 
of  the  serous  and  synovial  membranes,  sometimes  even  in 
that  which  penetrates  the  substance  of  the  organs,  and 
less  frequently  in  the  sub-cutaneous  cellular  texture. 
The  fibrous  texture  frequently  appears  also  in  the  lamel- 
lated  texture  ; we  find  examples  of  it  in  the  parietes  of 


CELLULAR  SYSTEM. 


41 


certain  cysts,  in  the  production  of  fibrous  tumours,  &c. 
It  is  to  the  transformation  of  this  texture  into  serous 
membrane  that  must  be  referred  the  production  of  most 
cysts,  which  are  developed  at  its  expense.  Motion  also 
produces  in  some  places  preternatural  serous  membranes. 

( Vide  Serous  System.)  Abscesses  and  old  fistulas  are 
lined  by  a membrane  which  has  some  analogy  with  those 
of  the  mucous  system. 

All  these  various  forms,  which  the  cellular  texture  can 
assume,  ought  not  to  surprise  us,  when  we  recollect  that 
the  fibre  which  constitutes  it  makes  at  the  same  time  the 
base  of  most  of  the  organic  systems. 

Degenerations,  properly  so  called,  are  very  common  in 
the  cellular  texture ; the  more  abundantly  an  organ  is 
provided  with  it,  the  more  is  it  exposed  to  this  kind  of 
affections.  But  they  do  not  only  attack  this  texture, 
when  it  is  found  combined  in  the  different  organs  with 
the  other  elements  of  which  they  are  composed,  but  the 
loose  cellular  texture  that  surrounds  them  is  equally  sub 
ject  to  them ; that  even,  which,  being  accumulated  in 
certain  regions,  seems  entirely  insulated  there,  is  not 
exempt  from  them.  Thus  in  the  white  swellings  of  the 
articulations,  in  the  cancerous  affections  of  the  glands  and 
of  the  viscera,  the  lamellated  texture  is  almost  always  con- 
founded with  the  diseased  parts  which  it  covers  and  is 
degenerated  like  them.  Thus  we  find,  in  the  places 
where  the  cellular  texture  is  accumulated,  schirrous,  car- 
cinomatous, tubercular  and  fungous  masses,  in  which  tlris 
texture  alone  appears  to  be  altei'ed. 

III.  Mterations  in  the  Development. 

The  cellular  texture  can  itself  be  developed  preter- 
naturally ; it  is  met  with  in  a great  number  of  moz’bid 
6 


42 


ADDITlOiSS  TO  THE  CELLULAR  SYSTEM, 


productions  ; many  of  them  are  essentially  formed  of  it. 
This  texture  takes  the  place  of  atrophous  organs  ; it  is 
produced  on  the  surface  of  suppurating  wounds,  in  which 
it  constitutes  the  membrane  of  the  fleshy  granulations. 
The  mechanism  of  its  formation  under  these  circum- 
stances is  far  from  being  perfectly  understood,  to  say  that 
it  is  an  extension,  an  elongation  of  the  cellular  texture 
which  pre-existed  in  the  part,  is  not  explaining  how  this 
sort  of  exuberance,  is  developed.  Every  thing  leads  us 
to  believe  that  it  is  a new  texture  foi'med,  as  in  the 
union  of  simple  wounds,  by  means  of  an  exudation  of  an 
albuminous  nature  or  at  least  of  one  capable  of  concre- 
tion. What  is  observed  in  fact  in  a solution  of  continuity 
which  is  cured  by  cicatrization  ? The  hemorrhage  ceases, 
the  blood  is  replaced  by  a serous  fluid,  the  wound  is 
covered  by  a soft  whitish  layer,  at  first  feebly  adhering 
to  it ; soon  this  substance,  to  appearance  inorganic,  is 
penetrated  with  vessels,  becomes  more  dense,  it  cannot 
be  separated  but  with  difficulty  from  the  subjacent  parts 
and  it  takes  all  the  characters  of  the  membrane  of  the 
■fleshy  granulations.  Has  not  this  series  of  phenomena 
the  greatest  analogy  with  what  takes  place  on  the  surface 
of  inflamed  serous  membranes  ? Do  we  not  see  in  both 
cases  an  effusion  of  lymph  capable  of  concretion,  the  re- 
sult of  which  is  the  production  of  a false  membrane, 
which,  by  becoming  organized,  is  changed  into  real  cel- 
lular texture  ? 


ADDITIONS 


TO  THE 

NERVOUS  SYSTEM  OF  ANIMAL  LIFE. 


Nerves  which  the  Brain  furnishes. 

Page  172. — “ The  cerebrum  furnishes  but  two  nerves, 

the  olfactory  and  optic  ; their  softness  is  greater 

than  that  of  most  of  the  other  nerves.” 

The  optic  nerve  is  placed  at  the  present  day,  among 
those  of  the  medulla  oblongata.  It  derives  its  origin  in 
fact  from  the  tubercles  which  surmount  the  posterior  part 
of  the  tuber  annulare ; tubercles  called  quadrigemina  in 
man,  though  there  are  but  two  of  them  in  many  animals, 
and  the  size  of  which  is  such,  in  many  classes,  as  birds 
and  fishes,  that  they  might  be  taken  for  cerebral  hemis- 
pheres. These  tubercles  which  deserve  to  be  called  optic 
rather  than  the  thalami  to  which  this  name  has  been 
given,  are  evidently  a dependance  of  the  cerebral  protu- 
berance, and  not  of  the  cerebrum,  as  some  anatomists 
have  said.  As  to  the  olfactory  nerve,  its  origin  is  not 


44 


ADDITIONS  TO  THE 


yet  well  known.  Animals  exhibit  it  to  us  coming  out  of 
an  accessory  part  which  their  cerebrum  has,  from  a kind 
of  lobe  superadded  to  its  hemispheres.  This  lobe,  some- 
times more  considerable  than  all  the  rest  of  the  cerebrum, 
is  formed  by  an  elongation  of  the  peduncles  which  extends 
forwards.  But  nothing  similar  appears  to  exist  in  man. 
The  olfactory  seems  to  be  detached  from  the  surface  of 
the  brain  itself.  Yet  some  anatomists  say  that  they  have 
traced  it  farther.  M.  Chaussier  makes  it  arise  from  the 
corpus  striatum,  and  others  have  seen  it  continued  with 
the  peduncles.  In  this  last  hypothesis,  and  by  reasoning 
from  analogy,  some  consider  the  pulpy  swelling  of  this 
nerve  as  its  real  point  of  origin.  This  swelling  would 
form  part  of  the  cerebrum  and  represent  the  olfactory 
lobe  of  animals  ; the  nerves  of  this  name  would  only  com- 
mence at  the  ethmoidal  canal. 

Origin  of  the  Nerves. 

Page  173. — “ It  is  clear,  that  the  nerves  do  not  arise 
deep  in  the  cerebral  substance,  at  least  in  an  apparent 
manner,  but  take  their  origin  from  its  external  surface.” 

Accurate  researches  have  demonstrated,  1st,  that  we 
can  trace,  to  a certain  depth,  the  filaments  of  the  origin  of 
most  of  the  nerves  both  spinal  and  cerebral  ; 2d,  that 
these  nerves  do  not  arise  from  the  medullary  substance, 
which  they  only  pass  through,  but  from  the  grey  substance, 
which  is  always  found  accumulated  in  the  neighbourhood 
of  the  places  where  they  are  sent  off,  as  Vicq-d’Azyr  has 
already  remarked.  These  truths  have  been  placed  be- 
yond a doubt  by  the  recent  labours  of  M.  Gall. 

The  mass  of  grey  substance  which  occupies  the  centre 
of  the  spinal  marrow  forms  there  on  each  side,  when  the 


NERVOUS  SYSTEM  OF  ANIMAL  LIFE. 


45 


marrow  is  cut  across,  two  arched  striae.  From  the  median 
line,  where  these  striae  are  united,  they  go  obliquely  out- 
wards, one  before  and  the  other  behind,  and  are  evidently 
continued  with  the  anterior  and  posterior  branches  of  the 
spinal  nerves.  In  other  words,  this  grey  substance  repre- 
sents in  the  marrow  two  species  of  prismatic  cords  united 
at  the  back  by  one  of  their  angles,  and  continuing  with 
the  nerves  by  the  other  two. 

In  examining  attentively  the  cerebral  nerves  at  their 
origin,  we  perceive  moreover  more  or  less  distinctly  the 
grey  substance  which  furnishes  them.  Sometimes  this 
substance  is  superficial,  as  at  the  origin  of  the  olfactory  and 
optic  nerves,  and  nothing  is  more  easy  than  to  see  the  me- 
dullary filaments  separating  from  it.  Sometimes  it  is 
deeply  situated,  and  it  is  only  by  a careful  dissection  that 
we  can  discover  the  true  origin  of  the  nervous  fibres, 
which,  breaking  off  on  a level  with  the  cerebral  substance, 
seem  to  arise  from  this  place.  Sometimes  the  nerve  is 
strengthened  in  its  course  by  the  addition  of  new  fila- 
ments which  come  to  it  from  the  neighbouring  parts  of 
the  cerebral  substance ; this  is  the  case  with  the  optic. 
There  exists  also  some  of  the  grey  substance  at  the  origin 
of  these  filaments. 

Nevertheless  we  ought  not  to  conclude  from  these  facts 
that  the  grey  substance  produces  the  nervous  filaments, 
and  it  is  no  doubt  in  a figurative  sense  that  M.  Gall  has 
called  it  the  originating,  or  nourishing  substance,  or 
matrix  of  the  nerves.  The  word  origin,  as  Bichat  has 
observed,  must  not  be  understood  literally.  Besides,  be- 
cause the  grey  substance  is  met  with  wherever  the  ner- 
vous is  continued  with  the  nervous  centres,  it  does  not 
follow  from  that,  that  one  is  made  by  the  other ; the 
union  of  these  two  substances  may  have  very  different 
uses. 


4b 


ADDITIONS  TO  THE 


Crossing  of  the  Nerves. 

Page  174. — I do  not  believe  that  with  our  present 
knowledge  we  can  explain  this  phenomenon”  (the  crossing, 
in  paralysis  from  compression  of  the  brain,)  “ and  the 
anatomical  opinion  pointed  out  above”  (viz.  that  the  nerves 
cross  at  their  origin)  “ is  contradicted  at  the  first  sight.” 

If  in  fact  the  crossing  of  the  nerves  at  their  origin  has 
been  rather  supposed  than  seen,  it  is  not  so  with  that  of 
the  spinal  marrow  which  Petit,  Lieutaud,  Winslow  and 
other  anatomists  have  admitted.  Raise  carefully  the  pia 
mater  which  covers  the  extremity  of  the  medulla  ob- 
longata, afterwards  separate  the  anterior  pyramidal  emi- 
nences, and  you  will  distinctly  see  the  medullary  fila- 
ments of  the  right  side  going  to  the  left,  directed  ob- 
liquely towards  the  cerebrum ; and  vice  versa,  those 
which  compose  the  left  pyramid  ascend  and  go  to  the 
right  side.  Above  this  crossing  in  the  form  of  a mat, 
the  pyramids  are  united  by  transverse  fibres,  which 
should  not  be  confounded  with  the  oblique  ones  here  re- 
ferred to. 

This  arrangement  enables  us  to  explain  how  the  lesions 
which  exist  above  this  place,  either  in  the  cerebrum  or 
the  medulla  oblongata,  produce  paralysis  in  the  side  op- 
posite to  the  afiected  one.  On  the  contrary,  when  the 
spinal  marrow  is  divided  transversely  and  on  one  side 
only,  the  same  side  is  paralyzed,  as  Yelloly  has  proved  ; 
Galen  had  before  noticed  this  fact. 

It  has  been  "said  that  in  some  cases,  paralysis  and  the 
cerebral  injury  which  was  the  cause  of  it,  have  been  seen 
to  occupy  the  same  side  of  the  body,  the  motions  being 
preserved  on  the  opposite  side.  It  i»  hardly  possible  to 


NERVOUS  SYSTEM  OF  ANIMAL  LIFE. 


47 


explain  these  insulated  facts,  at  least  to  admit  the  explana- 
tion which  M.  Gall  has  given.  This  explanation  is  found- 
ed upon  this,  that  among  the  fasciculi  which  go  fi’om  the 
spinal  marrow  to  the  cerebrum,  the  anterior  pyramids 
alone  cross.  Now,  by  supposing  that  the  cerebrum 
should  be  injured  in  a point  where  its  fibres  are  not  con- 
tinued with  those  of  the  pyramids,  the  phenomenon 
arising  from  the  crossing  will  not  take  place.  It  would 
remain  to  be  known  if  this  exception  is  met  with  in  the 
cases  observed  ; this  has  not  been  stated. 

Chemical  Composition  of  the  Nervous  System. 

Page  196. — ‘‘  This  hardening,  the  effect  of  acids,  of 

boiling  and  of  alkohol approximates  this  substance” 

(the  cerebral)  “ to  the  albuminous  fluids.  I say  that  it 
approximates  it,  for  there  are  still  great  differences  be- 
tween them,  of  which,  I think,  we  know'  but  little.” 

The  cerebral  substance  has  been  analyzed  by  modern 
chemists.  IVI.  Vauquelin  has  found  in  it,  1st,  two  pecu- 
liar fat  substances  united  to  a certain  quantity  of  phos- 
phorus ; 2d,  w’ater  which  forms  0,S0  parts  of  it ; 3d,  albu- 
men ; 4th,  osmazone ; 5th,  sulphur ; 6th,  phosphate  of 
potash,  lime  and  magnesia ; 7th,  some  appearances  of  the 
muriate  of  soda. 

Of  the  two  fat  substances,  one  is  white,  shining  and  of 
a soft  and  viscid  consistence.  It  is  distinguished  from 
fat,  properly  so  called,  by  its  crystalline  appearance,  by 
the  facility  with  which  alkohol  dissolves  it  and  by  the 
black  colour  it  assumes  w'hen  heated.  When  burnt,  a 
charcoal  is  left  for  a residuum  which  contains  phosphoric 
acid.  It  constitutes  0,45  of  the  substance  of  the  cere- 
brum. The  -other  fat  substance  is  much  less  abundant  in 


48 


ADDITIONS  TO  THE 


it,  and  differs  from  the  preceding  only  in  having  a red 
colour,  a strong  odour  and  taste  and  being  still  more 
soluble  in  alkohol. 

The  same  principles  are  found  in  the  spinal  marroAv  ; 
the  pi’oportion  of  fat  substance  is  greater  in  it ; there  is, 
on  the  contrary,  less  albumen,  osmazone  and  water.  The 
medulla  oblongata  exhibits  the  same  differences. 

It  is  the  albumen  which  predominates  in  the  nerves ; 
the  white  and  red  fat  substances  are  in  very  small  quan- 
tity in  them. 

Peculiar  Texture  of  the  Nervous  System. 

Page  199. — “ In  general  I think  that  this  substance,” 
(the  nervous)  “ as  well  as  the  cerebral,  would  be  ranked, 
if  they  were  deprived  of  the  vessels  that  run  through 
them,  rather  among  the  fluids  than  the  solids,  or  they 
would  form  a medium  of  connexion  between  the  two.” 

We  ought  to  distinguish  in  the  texture  peculiar  to  the 
organization  of  the  nervous  system,  the  two  substances 
which  it  contains,  the  white  and  the  grey. 

The  white  or  medullary  substance  is  evidently  com- 
posed of  fibres  in  many  parts  of  the  cerebrum  ; such  as 
the  corpus  striatum,  the  corpus  callosum,  the  tuber  annu- 
lare, the  elongations  which  it  sends  to  the  cerebrum  and 
to  the  cerebellum  and  the  termination  of  the  medulla 
oblongata.  Except  this  small  number  of  exceptions,  the 
cerebral  mass,  when  cut  in  all  directions,  seems  to  be 
perfectly  homogeneous,  and  is  uniform  in  appearance  ex- 
cept from  the  red  points  which  are  the  orifices  of  the 
divided  vessels  : there  is  no  very  distinct  filament  seen 
in  it.  Yet  we  shall  be  compelled  to  admit  the  existence 
of  filaments,  for,  if  we  endeavour  to  tear  the  white  sub- 


NERVOUS  SYSTEM  OF  ANIMAL  LIFE. 


49 


stance,  we  shall  see  that  it  resists  more  in  one  direction 
than  another.  But  if  instead  of  thus  dissecting  the  cere- 
brum by  cutting  it  irregularly,  we  attempt  to  trace  the 
course  of  the  apparent  fibres  to  its  inferior  part,  by  gently 
scraping  the  cerebral  substance  in  the  direction  of  these 
fibres,  we  shall  soon  acknowledge  that  they  extend  much 
further  than  we  at  first  thought.  We  shall  see  them 
penetrating  the  cerebral  mass  itself,  becoming  stronger 
there  and  contributing  by  their  union  to  form  those  emi- 
nences that  are  so  numerous,  those  fasciculi  so  variously 
formed,  between  which  we  do  not  at  first  find  any  kind 
of  connexion. 

It  was  by  pursuing  this  method  that  Malpighi  discover- 
ed the  real  structure  of  the  cerebrum,  so  well  developed 
since  by  Reil,  M.  Chaussier  and  M.  Gall.  Nothing  is 
easier  than  to  verify  the  facts  stated  by  these  anatomists, 
provided  we  could  have  a brain  of  a certain  consistence, 
such  as  would  be  that  of  a living  animal.  We  can  ren- 
der it  firmer  by  the  means  of  reagents.  We  cannot 
say  that  it  is  their  action  which  produces  an  appearance 
of  fibres,  for  with  very  dissimilar  liquids,  the  results 
are  uniform.  The  following  is  the  arrangement  which  is 
observed  : 

The  fibrous  fasciculi  which  constitute  the  termination 
of  the  medulla  oblongata,  having  arrived  at  the  inferior 
edge  of  the  tuber  annulare,  separate.  The  posterior  bo- 
dies go  to  the  cerebellum  in  which  they  terminate.  The 
anterior  pyramidalia  and  the  cords  coming  from  the  cor- 
pora olivaria,  traverse  the  tuber  annulare  by  passing  above 
its  transverse  fibres.  They  plunge  into  the  grey  sub- 
stance which  they  there  meet  with,  then  come  out  in 
front  of  the  pons  varolii,  and  are  extended  on  each  side, 
to  form  the  peduncles  or  crura  of  the  cerebrum  j the  me- 
dullary filaments  are  very  distinct  in  these  elongations, 
7 


50 


ADDITIONS  TO  THE 


because  they  are  mixed  with  the  grey  substance  which 
insulates  them.  These  filaments  become  larger,  when 
they  are  extended  across  the  optic  thalami  and  the  cor- 
pora striata.  Beyond  these  eminences,  the  fasciculi 
which  come  from  the  medulla  oblongata  spread  out  in 
each  of  the  cerebral  hemispheres ; their  fibres  go  in  all 
directions  and  extend  even  to  the  circumference  of  the 
organ.  Those  which  occupy  the  posterior  and  superior 
part  of  it  come  from  the  corpora  olivaria,  whilst  the 
pyramidalia  form  especially  the  anterior  and  inferior  part 
of  the  cerebrum. 

On  the  other  hand,  the  fibres  which  unite  the  hemi- 
spheres at  the  median  line,  as  those  of  the  corpus  callo- 
sum, the  fornix  and  the  anterior  and  posterior  commis- 
sures, do  not  appear  to  be  continued  with  the  fasciculi 
coming  from  the  medulla  oblongata.  Hence  the  distinc- 
tion of  the  diverging  and  the  converging  fibres,  or  appara- 
tus of  formation  and  apparatus  of  union,  (Gall)  called  also 
system  of  the  crura  of  the  cerebrum,  and  system  of  the 
corpus  callosum,  (Reil.)  Anatomists  are  not  agreed  re- 
specting the  origin  of  the  fibres  of  the  second  order ; per- 
haps it  differs  in  each  of  its  parts. 

The  cerebellum  has  also  two  orders  of  fibres.  The 
greater  part  of  its  mass  is  derived  from  those  which  come 
from  the  corpora  posteriora,  and  which  are  much  increased 
in  the  grey  substance  of  these  bodies.  Some  come  from 
the  fasciculi  which  the  cerebellum  receives  from  the 
tubercula  quadrigemina ; they  are  those  which  form  more 
especially  the  median  lobe,  or  the  superior  vermicular 
eminence,  as  Vicq-d’Azyr  first  demonstrated.  Finally 
others,  analogous  to  the  commissures  of  the  cerebrum, 
unite  the  two  lateral  lobes  by  forming  what  is  called  the 
Tons  Varolii,  whether  these  fibres  arise,  as  M.  Gall  thinks, 
from  the  external  grey  substance,  or  whether  they  are 


NERVOUS  SYSTEM  OF  ANIMAL  LIFE. 


51 


nothing  but  the  diverging  fibres  curved,  as  is  the  opinion 
of  Tiedemann. 

The  medullary  substance  of  the  nerves  is  formed,  like 
that  of  the  cerebrum,  of  fibres  in  juxta-position.  Accord- 
ing to  the  experiments  of  Reil,  this  fibrous  appearance  is 
not  owing  to  the  presence  of  the  neurilemas  which  can 
be  destroyed  with  acids  without  altering  the  filamentous 
texture. 

The  white  substance,  examined  in  the  spinal  marrow 
is  also  composed  of  filaments  ; Vieussens  was  among  the 
first  who  noticed  this  arrangement,  since  very  well  ob- 
served by  Monro  and  M.  Gall.  The  arrangement  of  the 
fibres  is  here  very  remarkable.  The  pia  mater  is  buried 
in  the  anterior  median  furrow,  and  continued  behind  into 
the  substance  of  the  spinal  marrow,  almost  to  its  posterior 
face ; from  each  side  of  this  elongation  many  grooved 
filaments  are  detached,  directed  from  above  below,  which 
contain  the  medullary  substance.  By  subjecting  the  spi- 
nal marrow  to  the  action  of  the  alkalies,  this  substance  is 
destroyed,  and  the  membranous  tubes  remain  untouched. 
There  is  then  a great  analogy  in  this  respect,  between  the 
structure  of  the  spinal  marrow  and  that  of  the  nerves  ; the 
pia  mater  performs  here  really  the  part  of  the  neurilema. 
If  the  consistence  of  the  spinal  marrow  is  increased  by 
acids,  the  fibres  which  compose  it  are  easily  distinguished. 
Most  of  them  are  longitudinal,  and  represent  an  infinite 
number  of  small  lamina,  formed  themselves  of  delicate 
filaments ; some  are  transverse.  These  last  are  seen 
especially  in  the  depth  of  the  anterior  median  furrow  ; 
the  posterior,  on  the  contrary,  exhibits  onl}’-  longitudinal 
fibres.  All  these  fibres  unite  and  anastomose  in  difierent 
ways,  as  the  nerves  do. 

The  grey  substance  does  not  form  like  the  white  a con- 
tinued whole  ; sometimes  exterior  to  this  last,  sometimes 


52 


ADDITIONS  TO  THE 


intermixed  with  its  fibres,  it  is  in  general  met  with, 
wherever  the  medullary  filaments  become  larger.  It  is 
found  in  the  whole  circumference  of  the  cerebrum,  and 
forms  what  is  called  the  cortical  substance  ; it  composes 
at  the  base  of  this  viscus  many  masses  which  have  been 
compared  to  ganglions.  It  occupies  the  centre  of  the 
spinal  marrow  ; it  has  been  said  that  the  nervous  extremi- 
ties are  provided  with  it,  but  this  has  by  no  means  been 
demonstrated.  . 

The  colour  of  this  substance  is  generally  of  a brownish 
grey,  in  some  parts  yellowish  and  even  black ; the  diver- 
sity of  these  shades  is  attributed  to  the  greater  or  loss’ 
quantity  of  blood  which  it  receives.  Its  density  is  less 
than  that  of  the  white  substance.  Its  structure  is  but 
little  known  ; some  have  admitted  that  there  were  fibres 
in  it ; Vicq-d’Azyr  has  traced  filaments  coming  from  the 
medullary  substance.  It  contains  many  blood-vessels, 
more  even  than  the  white  substance  ; but  it  is  not  entirely 
formed  of  them,  as  Ruysh  thought.  His  belief  arose 
from  the  fact  that  by  washing  this  substance,  after  having 
injected  it,  there  was  finally  nothing  left  but  vessels;  but 
it  is  evident,  that  in  this  case,  as  Albinus  observes,  the 
washing  takes  away  every  thing  that  is  not  vascular  or 
capable  of  injection. 

The  nervous  texture,  examined  by  the  microscope  ap- 
pears to  be  composed  of  globules  ; this  has  been  observed 
a great  number  of  times.  Prochaska,  Wenzel,  Barba, 
and  recently  M.  Bauer  have  paid  particular  attention  to 
these  globules.  In  order  to  see  them,  it  is  necessary  to 
mix  with  water  a small  quantity  of  the  white  substance 
and  place  it  in  the  focus  of  a strong  lens.  Their  size  has 
been  very  differently  estimated  ; it  has  been  compared,  as 
well  as  their  appearance,  to  that  of  the  colourless  globules 
which  are  found  in  the  blood.  Prochaska  thinks  them 


NERVOUS  SYSTEM  OF  ANIMAL  LIFE. 


53 


smaller  than  those  of  the  blood.  The  Messrs.  Wenzels 
brothers  think  that  they  are  hollow.  They  are  not  de- 
stroyed by  maceration  nor  by  reagents.  Their  union  ap- 
pears to  be  intimate  ; we  are  ignorant  of  the  mode  of  it ; it 
is  supposed  that  there  exists  between  them  a very  delicate 
cellular  texture,  containing  vessels ; others  have  thought 
that  they  saw  there  a fluid  and  viscid  matter.  Sometimes 
arranged  in  a row,  they  form  straight  parallel  lines ; some- 
times they  are  found  confusedly  heaped  together,  as  Pro- 
chaska  says  he  has  observed  in  the  grey  substance.  It  is 
no  doubt  from  this  difference  that  Cams,  rejecting  the  dis- 
tinction of  white  and  grey  substance,  says  that  the  organ- 
ization of  the  nervous  system  exhibits  but  two  essential 
modifications  ; in  the  one,  which  constitutes  the  gangli- 
form  or  central  masses,  the  nervous  substance  is  composed 
of  irregularly  scattered  points ; in  the  second,  which  com- 
prehends the  nerves,  they  are  regular  and  constant  lines. 
From  this  difference  of  organization,  he  deduces  the  dif- 
ferences of  action  of  the  two  s)^stems,  the  first  being  able 
to  act  by  irradiation,  whilst  the  other  is  limited,  in  this 
respect,  to  the  direction  of  its  length. 

The  colour  of  the  grey  substance  appears  to  reside  less 
in  the  globules  themselves,  than  in  the  species  of  soft 
cellular  texture  which  separates  them.  To  remove  the 
colouring  matter  from  this  substance,  it  is  merely  neces- 
sary to  put  it  in  tepid  water  in  thin  slices.  Sublimation 
produces  in  part  the  same  effect.  This  matter  does  not 
then  seem  to  be  inherent  in  the  globules. 

Development  of  the  Nervous  Centres. 

Page  2 37. — “ The  extreme  softness  of  the  brain  ren- 
ders its  dissection  v’^ery  difficult  in  the  foetus.” 


51 


AUDITIONS  TO  THE 


Tiedcmami  has  succeeded  in  overcoming  this  difficulty. 
This  author  has  traced  ail  the  changes  of  the  development 
ol  the  encephalon,  and  has  described  them  with  great 
precision.  Carus,  Doellinger  and  Ackermann,  had  pre- 
viously stated  some  facts  relative  to  the  development  of 
the  nervous  system.  M.  Serres  has  recently  been  en- 
gaged in  this  subject. 

The  brain  scarcely  exists  in  the  beginning;  in  an  em- 
bryo of  sis  weeks,  there  is  found  only  a flattened  cord 
which  represents  the  spinal  marrow,  and  the  superior 
extremit}^  of  which  is  slightly  enlarged. 

In  pregnancy  of  two  months,  the  brain  is  still  but  very 
little  developed  compared  with  the  spinal  marrow ; it  is 
then  composed,  1st,  of  the  cerebellum,  the  transverse  ex- 
tent of  which  is  considerable  ; 2d,  of  the  cerebrum,  which 
is  very  small  ; 3d,  of  a third  portion  placed  between  the 
two  first,  and  the  size  of  which  exceeds  that  of  the  cere- 
brum ; this  part  appears  to  correspond  to  the  cerebral 
protuberance,  or  more  exactly  to  the  tubercula  quadrige- 
mina.  M.  Serres  has  ascertained  that  it  is  formed  in  man 
and  animals,  before  the  cerebrum  and  cerebellum,  and 
immediately  after  the  spinal  marrow. 

'i’he  relative  dimensions  of  these  organs  afterwards 
change.  Tlie  cerebrum  grows  more  and  more  ; towards 
the  fifth  month,  it  already  covers  a part  of  the  protuber- 
ance : at  the  sixth,  it  extends  even  upon  the  cerebellum, 
which  it  gets  beyond  at  the  seventh.  The  other  parts  on 
the  contrary  increase  less  in  proportion,  especially  that 
ivhich  coz'responds  to  the  protuberance. 

The  whole  encephalon  is  divided  at  first  into  two  parts 
by  a longitudinal  furrow  ; this  arrangement  is  observed 
in  foetuses  of  seven  months.  The  two  halves  afterwards 
approximate  and  finally  unite,  except  in  some  places, 
where  the  interstices  form  cavities ; so  that  at  three  months 


NERVOUS  SYSTEM  OF  ANIMAL  LIFE. 


55 


we  discover  instead  of  a longitudinal  division,  1st,  the 
third  ventricle  ; 2d,  the  aqueduct  of  Sylvius  v^^hich  is,  at 
this  period,  a great  cavity  continuous  with  the  middle 
ventricle ; 3d,  the  fourth  ventricle.  Afterwards  the  cavity 
of  the  aqueduct  is  gradually  contracted  ; it  is  nothing  but 
a canal  towards  the  seventh  month.  The  two  other  cavi- 
ties undergo  no  ulterior  changes  but  those  which  belong 
to  the  development  of  the  parietes. 

In  the  first  periods  of  gestation,  the  conformation  of 
the  cerebrum  is  very  simple  ; there  then  exists  but  the 
base  of  this  viscus,  and  that  even  is  very  imperfect.  We 
see  in  a foetus  of  seven  weeks  only  the  thalami  nervorum 
opticorum,  the  corpora  striata  are  hardly  visible  ; a sort 
of  membranous  part  seems  to  indicate  the  place  of  the 
hemispheres. 

It  is  in  fact  under  the  form  of  a membrane  that  each, 
hemisphere  is  developed  ; this  membrane,  originating  at 
the  base  is  bent  before  and  belpnd,  as  it  is  seen  at  the 
ninth  week,  and  extends  to  the  corpora  striata  and  the 
thalami  nervorum  opticorum  ; the  space  which  remains 
below  them  constitutes  the  lateral  ventricles.  The  an- 
terior lobes  appear  first ; they  are  very  visible  at  three 
^ months.  The  corpus  callosum  is  formed  almost  at  the 
same  time,  by  the  junction  of  the  two  membranes  of  the 
hemispheres ; it  occupies  at  first  only  their  anterior  part, 
and  is  extended  backwards  as  they  grow  ; at  six  months 
it  only  extends  half  their  length.  The  cornua  Ammonis 
appear  with  the  corpus  callosum,  as  well  as  the  fornix, 
the  mamillar)''  eminences,  the  posterior  commissure,  and 
the  peduncles  of  the  cerebrum,  shortly  after  is  discovered 
the  hippocampus  minor  and  the  groove  which  gives  rise 
to  it,  the  pineal  gland  and  its  peduncles,  then  the  ante- 
rior commissure,  the  septum  lucidum  and  its  cavity,  which 
then  communicates  with  the  third  ventricle,  between  the 


56 


ADDITIONS  TO  THE 


two  pillars  of  the  fornix  ; in  the  last  place,  the  semi- 
circular band,  the  plexus  choroides  and  the  infundibulum  ; 
this  successive  evolution  is  completed  towards  the  seventh 
month. 

All  these  parts  have  not  the  same  appearance  in  the 
different  periods  of  their  development ; thus  the  fornix 
is  at  first  composed  of  two  cords  insulated  in  their  whole 
extent ; thus  the  corpora  striata  are  for  a long  time  larger 
than  afterwards  and  of  a different  form.  At  the  third 
month,  the  lateral  ventricles  are  open  at  their  internal  and 
posterior  part ; we  can,  even  towards  the  fourth  month, 
penetrate  into  their  interior  by  turning  back  the  mem- 
brane which  forms  them.  At  the  fifth,  their  extent  is 
considerable,  owing  to  the  small  degree  of  thickness  of 
their  parietes  ; they  progressively  diminish,  as  these 
parietes  are  developed.  The  surface  of  the  cerebrum  is 
smooth  in  the  first  months  ; soon  the  fissure  of  Sylvius  is 
visible,  some  inequalities  appear,  and  the  circumvolutions 
are  formed  at  the  seventh  or  eighth  month. 

The  cerebellum,  in  an  embryo  of  seven  weeks,  appears 
like  a fine  lamina,  stretched  horizontally  from  each  side 
of  the  fissure  which  divides  the  encaphalon  at  this  period, 
and  continuing  on  the  one  hand  with  the  spinal  marrow, 
and  on  the  other  with  the  cerebral  protuberance.  This 
lamina,  bent  backwards,  forms  towards  the  fourth  month 
a great  cavity  continuous  with  the  fourth  ventricle  ; it 
afterwards  becomes  thicker  and  the  cavity  diminishes. 
This  is  reduced  to  the  fourth  ventricle  towards  the  fifth 
month  : transverse  furrows  then  divide  the  cerebellum 
into  five  lobes.  The  structure  of  this  viscus  is  more  and 
more  developed.  The  lamina  are  very  distinct  at  the 
seventh  month. 

The  cerebral  protuberance  would  be  better  called  in  the 
beginning  the  mass  of  the  tubercula  quadrigemina  ; its 


NERVOUS  SYSTEM  OF  ANIiMAL  LIFE, 


57 


inferior  part  or  Pons  Varolii  is  wanting,  there  only  exists 
the  lamina  which  is  afterwards  surmounted  by  the  tuber- 
cula.  This  part  is  hollowed  out  from  the  aqueduct  or 
cavity  of  Sylvius,  and  exhibits  a groove  which  is  the 
trace  of  the  division  which  is  early  observed.  The  tuber 
annulare,  properly  so  called,  begins  to  appear  in  the  course 
of  the  fourth  month,  but  its  development  is  not  complete 
till  the  seventh  ; it  is  also  at  this  period  only  that  the 
tubercula  appear. 

The  spinal  marrow  forms  at  first  a species  of  ribbon, 
divided  by  the  common  fissure  and  occupies  the  whole 
length  of  the  vertebral  canal,  extending  to  the  os  coccygis. 
In  the  third  month,  its  edges  turn  over  behind  and  unite, 
bjr  which  means  a canal  is  formed  which  is  continuous 
with  the  fourth  ventricle.  At  t\velve  weeks,  the  termi- 
nation of  the  medulla  oblongata  is  very  evident ; we  see 
there  the  posterior  pyramidalia  which  are  continued  with 
the  cerebellum  and  the  anterior  ones  making  a continua- 
tion with  the  peduncles  of  the  cerebrum.  It  is  at  the 
third  month,  according  to  M.  Serres,  that  the  medulla  is 
contracted  and  reaches  by  degrees  to  the  level  of-  the 
second  lumbar  vertebra.  At  the  fifth,  we  distinguish  the 
cervical  and  lumbar  enlargements  as  well  as  the  cauda 
equina ; the  canal  of  the  medulla  still  evidently  commu- 
nicates with  the  fourth  ventricle. 

Such  are  the  principal  changes  which  take  place  in  the 
conformation  of  the  encephalon.  Those  which  it  expe- 
riences in  its  texture  are  not  less  remarkable. 

All  is  fluid  and  homogeneous  in  the  beginning.  The 
white  substance  afterwards  becomes  more  distinct.  Its^ 
fibrous  structure  is  early  manifested  ; the  interlacing  of 
the  pyramidalia  is  seen  at  the  eighth  week,  according  to 
M.  Serres.  Tiedemann  has  seen  at  the  fourth  month 
fibres  in  these  pyramidalia,  and  shortly  after  in  the  fasci- 
S 


58 


ADDITIONS  TO  THE 


culi  of  the  olivaria  ; these  fibres  can  be  traced  in  the  tha- 
lami  nervorum  opticorum  and  in  the  corpora  striata  ; they 
extend  out  in  rays  to  form  the  membrane  of  the  hemi- 
spheres. These  diverging  fibres  become  more  and  more 
evident ; at  the  sixth  month,  they  are  almost  naked  on 
the  parietes  of  the  lateral  ventricles.  At  the  same  period, 
the  cerebral  substance  has  appeared,  through  the  micros- 
cope, to  be  composed  of  globules  immediately  below  the 
pia  mater,  and  of  fibres  lower  down.  At  the  seventh 
month,  a section  of  the  ventricles  exhibits  very  evident 
layers  of  radiated  fibres.  New  ones  are  afterwards  pro- 
duced which  form  the  circumvolutions  ; they  seem  to 
arise  from  the  external  pia  mater  and  are  joined  at  a right 
angle  to  the  first ; these  are  called  the  converging  fibres. 
At  the  ninth  month,  the  organization  is  completed. 

The  grey  substance  does  not  appear  till  a long  time 
after  the  white.  It  is  not  until  from  the  sixth  to  the 
seventh  month  that  the  cords  of  the  corpora  olivaria  form 
real  eminences,  hy  the  development  of  this  substance  in 
their  interior ; the  pyramidalia  are  enlarged  a month 
sooner.  In  the  last  periods  of  gestation,  the  canal  of  the 
spinal  marrow  is  also  filled  with  a grey  substance  ; the 
same  substance  is  developed  in  the  circumvolutions  of  the 
cerebrum,  in  the  cerebellum,  &c.  ; its  colour  is  not  very 
evident  in  all  these  parts  till  the  ninth  month.  M.  Serres, 
as  well  as  Tiedemann,  thinks,  that  the  white  substance 
arises  before  the  grey  in  the  spinal  marrow  ; but  it  is  not 
the  same,  according  to  him  in  regard  to  the  cerebrum  ; 
he  considers  the  optic  thalamus  and  the  corpus  striatum 
as  entirely  formed  of  grey  substance  in  the  beginning  ; 
the  white  is  not  developed  till  afterwards.  The  grey  and 
white  substances  are  always  preceded  in  their  develop- 
ment, by  that  of  the  red  vessels  in  the  places  where  they 
are  produced. 


NERVOUS  SYSTEM  OF  ANIMAL  LIFE. 


59 


Development  of  the  Nerves. 

Page  237. — “ The  nerves  of  animal  life  have  a devel- 
opment proportional  to  that  of  the  brain.” 

This  relation  is  very  different  in  the  beginning,  for  we 
distinguish  the  spinal  marrow  and  the  brain,  whilst  most 
of  the  nerves  are  wanting,  on  account  of  the  late  develop- 
ment of  the  other  systems.  We  know  not  if  it  be  the 
same  with  the  heart  and  the  digestive  canal,  which  are 
formed  almost  as  soon  as  the  nervous  system.  M.  Meckel 
thinks  that  the  nerves  of  these  organs,  like  those  of  the 
other  parts,  do  not  appear  until  after  the  nervous  centres. 
Yet  the  great  sympathetic  appears  to  exist  very  early, 
and  is  developed  if  not  sooner,  as  Ackermann  thinks,  at 
least  at  the  same  time  as  the  brain  and  spinal  marrow. 
Another  exception  to  this  rule  is,  that  we  find,  in  a month 
after  conception,  the  intercostal  nerves  as  well  as  the  ver- 
tebral ganglions  ; now,  neither  the  brain  nor  the  marrow 
are  distinct  at  this  period.  Perhaps  the  filaments  of  the 
great  sympathetic  being  more  transparent  escape  observa- 
tion. This  nerve  is  found  in  foetuses  which  are  born 
entirely  destitute  of  all  the  parts  of  the  encephalon. 

In  a foetus  of  three  months  is  seen  distinctly  the  optic 
and  olfactory  nerves.  In  the  following  month  the  fifth 
pair  is  visible.  At  the  seventh,  the  origin  of  all  the 
nerves  is  seen  perfectly  well.  The  olfactory  nerves  are 
at  first  very  lai’ge,  they  begin  to  diminish  at  the  sixth 
month.  The  spinal  nerves  are,  like  the  cerebral,  very 
distinct  at  their  origin  before  the  grey  substance  is  dis- 
coverable, (Tiedemann.) 

The  texture  of  the  nerves  does  not  become  apparent, 
until  their  vessels  are  developed. 


60 


ADDITIONS  TO  THE 


MORBID  ANATOMY  OP  THE  NERVOUS  SYSTEM  OF  ANIMAL 

LIFE. 

I.  Alterations  in  the  External  Forms. 

Organic  diseases  often  increase  the  size  of  the  nerves, 
as  Reimarus  has  observed  with  regard  to  white  swellings. 
Neuralgias  are  sometimes  accompanied  with  the  same 
alterations.  Cotugno  has  found  the  sciatic,  in  the  neural- 
gia of  this  name,  as  if  it  were  infiltrated  with  gelatinous 
matter.  Fat  also  may  accumulate  between  the  nervous 
fibres.  A sort  of  atrophy  of  the  nerves  is  on  the  contrary 
tlie  result  of  some  paralyses  or  of  pressure  too  long  con- 
tinued ; thus  in  amaui'osis,  the  optic  nerve  is  often  har- 
dened like  horn,  and  gradually  reduced  to  its  neurilema ; 
thus  various  tumours  produce  atrophy  of  the  nerves  which 
they  compress.  The  brain  appears  to  have  experienced 
a diminution  of  size  in  the  cases  stated  by  Littre  and  Sa- 
batier, in  which  after  a powerful  concussion,  this  viscus, 
the}'  assure  us,  no  longer  fdled  the  cavity  of  the  cranium. 
M.  Cruveilhier  has  seen  the  same  thing  in  the  dead  body 
of  an  idiot. 

The  nerves  have  sometimes  appeared  to  be  less  con- 
sistent than  in  the  natural  state.  Weinhold,  as  cited  by 
Hufeland,  has  found  in  them  after  typhus,  a peculiar  soft- 
ness and  flacciditjL  They  exhibit,  it  is  said,  this  altera- 
tion in  dropsies  and  fatal  hemorrhages. 

The  brain  presents  the  two  extremes  in  relation  to  its 
consistence  ; its  hardness  is  seen  in  mania,  idiocy  and 
epilepsy ; its  Softness,  observed  at  first  in  the  same  cir- 
cumstances, has  been  since  seen  in.  ataxic  and  adynamic 
fevers  and  in  hydrocephalus.  M.  Rosfan  has  given  some 


NERVOUS  SYSTEM  OF  ANIMAL  LIFE. 


6i 


new  details  upon  this  last  alteration  and  upon  the  disease 
which  results  from  it.  In  the  cases  which  he  has  ob- 
served, the  softening  varies  much  in  relation  to  its  extent, 
depth,  intensity,  colour  of  the  cerebral  substance,  &c. 
M.  Lallemand  has  also  described  this  alteration. 

The  spinal  marrow  loses  its  consistence  in  spina-bifida. 
Softness  of  the  marrow  has  recently  been  met  with  by 
M.  Scipio  Pinel,  in  cases  where  it  appeared  to  have.pro- 
duced  peculiar  symptoms.  Frank  has  found  this  organ 
hardened. 

Tumours,  such  as  aneurisms,  situated  upon  the  course 
of  the  nerves,  may  displace,  distend  and  flatten  them.  It 
is  known  how  they  yield  under  these  circumstances. 
Perhaps  their  elongation  may  be  in  great  measure  attri- 
buted to  the  kind  of  unfolding  which  they  undergo.  The 
nerves  are  in  fact  folded  in  the  natural  state  ; their  sur- 
face is,  at  it  were,  wrinkled  ; by  examining  it  attentively, 
we  can  discover  there  an  innumerable  quantity  of  small 
striaj,  transverse  in  most,  oblique  in  others,  interlaced  in 
some,,  forming  zig-zags,  spirals,  &c.  These  striae  are  re- 
markable for  their  yellowish  or  fawn  colour,  which  forms 
a contrast  with  the  pearl  white  which  the  nerve  preserves 
in  their  interstices.  This  is  at  first  view  so  striking,  that 
we  only  see  at  first  a multitude  of  white  threads,  arranged 
precisely  like  the  striae  ; the  deeper  colour  of  these  last 
prevents  them  from  fixing  the  attention  so  much.  Now 
these  striae  are  effaced  by  extension  and  reappear  when  it 
is  taken  off.  The  same  thing  then  should  take  place  in 
the  cases  of  which  we  have  spoken. 

The  brain  and  spinal  marrow  are  exposed  to  compres- 
sions, which  alter  more  or  less  their  form.  The  marrow 
in  particular  undergoes  at  tim.es  remarkable  bendings ; 
its  functions  are  not  always  deranged  by  them.  The  form 
of  the  brain  also  experiences  very  great  changes  in  hydro- 
cephalus. 


62 


ADDITIONS  TO  THE 


II.  Alterations  in  the  Organization. 

Inflammation  of  the  nerves  is  a very  rare  disease.  Can 
we  give  this  name  to  the  sanguineous  engorgements,  vas- 
cular dilatations,  which  their  surface  exhibits  in  certain 
cases,  in  typhus,  for  example  ? To  be  certain  of  the  na- 
ture of  these  engorgements,  it  is  necessary  to  destroy  the 
neurilema  by  an  acid,  and  observe  what  is  then  the  colour 
of  the  medullary  substance.  Reil,  who  has  followed  this 
course  in  many  cases,  has  found  the  nervous  medulla  of 
a red  colour  and  evidently  inflamed.  Suppuration,  gan- 
grene and  ulceration  can  affect  the  nerves,  but  they  never 
do  primarily.  The  brain,  on  the  contrary,  is  often  the 
seat  of  purulent  collections ; gangrene  sometimes  seizes 
upon  it,  as  is  seen  particularly  after  wounds  of  the  head, 
when  this  viscus  is  injured  or  merely  laid  bare  ; we  re- 
move it  then  by  spoonsful,  in  the  form  of  an  extremely 
fetid,  grey  sanies.  False  membranes  are  produced  in  the 
brain,  especially  upon  the  parietes  of  the  abscesses  which 
occupy  its  interior.  They  are  susceptible  of  being  organ- 
ized and  beco7ning  vascular. 

The  mode  of  reunion  of  the  nerves,  when  they  are 
divided,  has  been  a subject  of  discussion.  Arnemann  has 
described  it  with  much  care.  Shortly  after  the  division, 
the  superior  end  swells  at  its  extremity,  and  forms  a kind 
of  greyish  knot,  elongated  and  very  hard  ; the  inferior 
swells  also  but  less,  then  both  unite  and  their  separation 
disappears.  The  knot  continues  and  often  even  acquires 
a consistence  almost  cartilaginous.  The  portion  of  the 
nerve  which  is  below  also  undergoes  some  changes, 
though  all  observers  are  not  agreed  upon  this  point.  In 
general  it  becomes  more  slender,  is  withered,  as  it  were. 


NERVOUS  SYSTEM  OF  ANIMAL  LIFE. 


63 


its  colour  changes  and  its  folds  are  effaced.  As  to  the 
nature  of  the  cicatrix,  most  authors  think  it  nervous,  and  as 
such,  capable  of  re-establishing  the  continuity  of  the  nerve 
in  relation  to  its  functions.  Haighton  has  even  made  ex- 
periments upon  this  subject,  which  appear  to  be  decisive. 
After  having  cut  in  a great  number  of  dogs  the  two  nerves 
of  the  eighth  pair,  either  at  the  same  time,  or  one  after 
the  other,  but  with  only  a few  days  between,  and  having 
thus  ascertained  that  death  was  uniformly  the  consequence, 
he  allowed  in  another  dog  six  weeks  to  elapse  between 
the  section  of  the  two  nerves.  The  animal  recovered 
perfectly.  We  may  conclude  from  this,  either  that  the 
cicatrix  of  the  first  divided  nerve  transmitted  the  nervous 
influence,  or  that  the  functions  of  this  nerve  were  re- 
established between  the  first  and  second  operation,  by 
means  of  anastomoses.  To  remove  every  kind  of  doubt, 
the  two  reunited  nerves  were  cut  a second  time  in  the 
same  animal  and  he  died.  Then  it  was  by  means  of  the 
cicatrix  that  he  had  lived.  Arnemann  denies  to  the  cica- 
trices of  the  nerves  the  property  of  the  nerves  ; they  are, 
according  to  him,  purely  cellular,  and  w’hen  the  functions 
of  the  nerve  are  re-established,  it  is  because  there  is  an 
immediate  reunion  between  the  two  ends ; but  w'hen 
these  ends  are  separated,  or  there  is  a loss  of  substance, 
he  denies  that  a regeneration  can  take  place.  The  knot 
which  is  produced  appears  to  him  to  be  incapable  of  re- 
placing the  nervous  substance ; he  has  seen  it  arise  from 
the  cellular  texture  and  only  gradually  unite  with  the  two 
ends  of  the  nerve.  Yet  Fontana,  Michaelis  and  Mayer 
say,  that  they  have  traced  nervous  filaments  through  the 
regenerated  portion.  These  filaments  are  evidently  con- 
tinued with  the  nerve.  Treated  with  nitric  acid,  far 
from  being  destroyed  by  it,  they  are  hardened,  like  the 
medullary  substance  under  similar  circumstances,  (Mayer.) 


64 


ADDITIONS  TO  THE 


Now  these  physiologists  have  removed  one,  two,  six 
lines,  and  even  an  inch  of  the  length  of  the  nerve. 

In  amputations,  the  superior  end,  which  forms  part  of 
the  stump,  swells  as  in  the  preceding  case.  M.  Lobstein 
has  given  new  details  upon  this  fact,  which  had  been  ob- 
served by  Vanhoorn. 

Lesions  of  the  brain  appear,  like  those  of  the  nerves, 
to  be  followed  by  a sort  of  regeneration.  Solutions  of 
continuity  of  another  kind  have,  moreover,  their  seat  in 
this  viscus.  These  are  the  internal  lacerations,  in  conse- 
quence of  which  the  blood  is  effused  either  in  the  cerebral 
substance,  or  in  the  ventricles  ; concussions  of  the  brain 
and  apoplex'y  offer  examples  of  them.  The  blood  then 
becomes  a foreign  body,  whose  presence  occasion  serious 
difficulties.  These  difficulties  should  also  be  in  part  at- 
tributed to  this,  that  the  cerebral  substance  is  disorganized 
in  a greater  or  less  extent ; its  colour  is  a yellowish  red, 
and  its  texture  is  softened.  When  death  is  not  the  con- 
sequence of  it,  a membrane  is  formed  around  the  blood, 
this  fluid  is  absorbed,  and  there  remains  only  a serous 
cyst,  which  also  finally  disappears.  The  spinal  marrow 
is  likewise  liable  to  experience  this  alteration  ; it  was 
converted  into  a sort  of  porridge  infiltrated  with  blood, 
in  a case  observed  by  M.  Gaultier  de  Claubry. 

The  nerves  are  hardly  ever  ossified.  The  brain  is  so 
sometimes  ; various  instances  of  which  are  found  in  au- 
thors. They  are  almost  alwa3"s  osseous  productions,  for 
the  most  part  loose,  rarely  adhering  closely  to  the  cerebral 
substance.  Tumours,  which  seem  to  belong  to  the  fibrous 
or  cartilaginous  textures,  are  developed  in  the  nerves,  the 
brain  and  even  the  spinal  marrow.  They  are  hard,  grej^- 
ish  and  separate  the  medullary  fibres,  which  take  no  part 
in  their  development.  M.  Dubois  and  Home  have  extir- 
pated these  tumours.  Some  refer  them  to  the  cancer  of 


NERVOUS  SYSTEM  OF  ANIMAL  LIFE. 


65 


the  nerves.  Cysts  are  formed  in  the  brain  ; we  have 
already  pointed  out  one  of  the  circumstances  under  which 
they  are  produced.  They  are  often  taken  for  hydatids. 
These  are  rare  in  man,  though  they  are  sometimes  found. 

The  scrophulous  affection  is  the  most  common  in  the 
brain.  It  appears  under  the  form  of  tubercles  of  very 
various  size,  round,  greyish  or  yellow,  soft  and  brittle, 
the  number  of  which  is  sometimes  very  considerable.  A 
cellular  membrane  surrounds  them.  Cancer  of  the  brain 
has  also  been  observed.  Finally  M.  Meckel  speaks  of 
fungous  and  spongy  tumours,  analogous  to  the  productions 
called  erectile,  and  which  have  their  seat  in  this  viscus. 
They  are  extremely  rare  in  it.  The  nerves  are  foreign 
to  almost  all  these  alterations. 

III.  AUerations  in  the  Development. 

Clarke  has  given,  in  the  Philosophical  Transactions, 
the  description  of  a foetus  so  imperfect,  that  it  had  no 
nervous  system.  It  is  the  only  fact  of  the  kind  known. 
We  often  meet  with  acephalous  foetuses,  or  rather  aence- 
phalous  ones,  that  is  to  say,  destitute  of  a part  or  of  the 
whole  of  the  brain.  The  spinal  marrow  exists  in  the 
greatest  number  of  cases,  but  in  some  it  also  is  wanting. 
Examples  of  this  last  kind  are  cited  by  M.  Lallemand  in 
his  inaugural  dissertation.  I have  myself  seen  some.  In 
these  cases,  the  peculiar  membrane  of  the  spinal  marrow 
forms  the  parietes  of  a cavity  which  contains  a liquid,  and 
the  nerves  are  implanted  as  usual  into  this  membrane. 
Otto,  ( Treatise  on  Morbid  Anatomy ,)  mentions  many 
cases  in  which  the  optic  nerve  and  other  nerves  of  the 
senses  were  wanting  in  individuals  destitute  of  sight, 
hearing,  &c. ; the  rest  of  the  nervous  system  was  as  in 
the  natural  state. 

9 


66 


ADDITIONS,  &c. 


Anomalies  are  quite  rare  in  the  nervous  system,  espe* 
cially  in  the  portion  of  it  which  belongs  to  animal  life. 
Yet  the  brain  sometimes  exhibits  an  inequality  in  the  size 
of  its  lobes.  Bichat  was  himself  a remarkable  example 
of  this.  Hydrocephalus  is  most  often  a congenital  affec- 
tion. The  canal  of  the  spinal  marrow  sometimes  continues 
until  after  birth,  as  M.  Portal  and  others  have  seen  in 
hydrorachitis.  The  nerves  vary  a little  in  their  distribu- 
tion, though  it  is  more  uniform  than  that  of  the  arteries. 

The  nervous  texture  is  never  preternaturally  produced, 
if  it  be  not  in  the  case  of  the  wound  of  which  we  have 
spoken  above. 


ADDITIONS 


TO  THE 


NERVOUS  SYSTEM  OF  ORGANIC  LIFE. 


Insulation  of  the  Great  Sympathetic. 

Page  252. — “ It  is  evident  that  a line  of  demarcation 
separates  the  nerves  of  the  ganglions  and  those  of  the 
brain,  and  that  the  method  is  inaccurate  which  considers 
them  as  forming  a single  nerve,  arising  by  some  origin 
from  this  last.” 

The  great  sympathetic  has  always  been  a subject  of  dis- 
cussion among  anatomists.  Haller,  Zinn,  Scarpa  and  Legal- 
lois  have  maintained,  that  it  depended  on  the  brain  and  the 
spinal  marrow,  like  the  other  nerves,  and  that,  like  them, 
it  only  transmitted  an  influence  which  it  receives  from 
these  parts.  Many  other  physiologists,  on  the  contrary, 


6S 


ADDITIONS  TO  THE 


think  that  this  nerve  is  insulated,  by  its  arrangement  as 
well  as  by  its  action,  from  the  rest  of  the  nervous  system. 
Authenrieth  makes  it  come  from  the  general  nervous  sys- 
tem ; but  he  supposes  that  as  its  filaments  pass  through 
the  ganglions,  they  are  less  and  less  subjected  to  the  cere- 
bral action.  According  to  Reil,  the  great  sympathetic  has 
only  filaments  of  communication  and  no  origin,  but  it 
enjoys  the  property  of  a semi-conductor.  Gall,  like 
Bichat,  makes  a multitude  of  insulated  systems  of  it,  which 
arises  from  the  manner  in  which  he  has  considered  the 
nervous  system  in  general.  Finally  .1.  F.  Meckel  has 
adopted  a sort  of  mixed  opinion  according  to  which  the 
great  sympathetic,  though  insulated,  may  depend,  to  a 
certain  extent,  upon  the  central  organs. 

It  would  be  superfluous  to  give  in  detail  here  the  rea- 
sons alleged  for  and  against  these  opinions  ; we  shall  con- 
tent ourselves  with  pointing  out  the  principal.  Nothing 
prevents  us  from  calling,  in  the  great  sympathetic  nerve, 
points  of  origin,  the  points  of  communication  of  this  nerve 
with  the  spinal  marrow  and  the  brain,  if  we  recollect 
what  ought  to  be  understood  by  the  term  origins  in  the 
nervous  system  ; they  are  the  central  extremities  of  the 
nerves,  those  which  are  the  nearest  the  nervous  centres. 
All  that  has  been  said  to  prove  that  the  ganglions  are 
these  centres,  only  shows  that  there  are  great  differences 
of  organization  in  the  great  sympathetic  and  the  other 
nerves.  It  is  unimportant  whether  this  series  of  gan- 
glions and  intermediate  cords  is  considered  as  a single 
nerve,  or  as  so  many  insulated  parts,  united  by  anasto- 
moses. But  it  is  not  so,  to  know  if  this  system  be  really 
independent  of  the  cerebral,  or  if,  as  Legallois  pretended, 
it  be  on  the  contrary  from  this  last  that  it  derives  all  its 
influence.  We  know  the  experiments  of  this  physiolo- 
gist upon  animals  from  which  he  removed  the  brain  and 


NERVOUS  SYSTExM  OF  ORGANIC  LIFE. 


69 


afterwards  supported  life  by  means  of  artificial  respiration. 
The  destruction  of  the  spinal  marrow  constantly  produced 
death  by  the  sudden  cessation  of  the  pulsations  of  the 
heart.  When  the  spinal  marrow  was  destroyed  only  in 
part,  the  pulsations  were  only  weakened,  cutting  off  the 
limbs  did  not  occasion  the  blood  to  flow,  but  life  still 
continued.  Legallois  concludes  from  them,  1st,  that  the 
heart  receives  the  principle  of  its  action  from  all  the  points- 
of  the  spinal  marrow,  through  the  medium  of  the  great 
sympathetic  ; 2d,  that  the  integrity  of  the  spinal  marrow 
is  indispensable  to  the  functions  of  this  last.  But  we 
have  seen  monsters  born  without  a spinal  marrow,  and 
yet  they  lived  in  the  womb  of  the  mother.  Dr.  Wilson 
Philip  having  repeated  the  experiments  which  we  have 
just  cited,  found  that  the  pulsations  did  not  cease  imme- 
diately after  the  spinal  marrow  had  been  removed  ; they 
ceased  quicker  when  it  was  violently  torn  out  than  when 
it  was  taken  away  with  care.  The  animals,  subjected  to 
these  experiments,  resist  also  in  general  so  much  the 
more  in  proportion  as  they  are  younger.  Finally,  in 
many  fishes,  carps  in  particular,  Mr.  Clift  has  seen  the 
pulsations  of  the  heart  continue  notwithstanding  the  lesion 
of  the  spinal  marrow.  We  ought  tiien  to  have  regard,  in 
the  conclusions  which  we  draw  from  this  sort  of  experi- 
ments, to  the  age  and  species  of  the  animal.  We  may 
apply  to  the  spinal  marrow,  in  this  last  respect,  what  is 
elsewhei’e  said  of  the  brain  ; it  is,  that  in  the  inferior  ani- 
mals, the  centres  are  much  less  necessary  to  the  action  of 
the  rest  of  the  nervous  system.  Their  less  importance  in 
animals  accords  with  their  less  development.  So  in  man 
and  the  superior  animals,  the  great  sympathetic  depends 
so  much  the  less  on  the  brain  and  the  spinal  marrow,  as 
these  parts  are  themselves  less  developed,  as,  in  a word, 
the  individual  is  younger.  It  is  in  this  way,  and  not  in 


70 


ADDITIONS  TO  THE 


an  absolute  manner,  that  we  should  resolve  the  question 
proposed. 

Structure  of  the  Ganglions. 

Page  258. — “ I think  then  by  admitting,  even  to  a 
certain  extent,  the  internal  arrangement  that  this  author 
'(Scarpa)  has  observed  in  the  ganglions,  we  cannot  describe 
these  organs  in  the  point  of  view  in  which  he  has  present- 
ed them.” 

The  observations  made  by  Scarpa  have  been  repeated 
in  our  time.  The  ganglions  are  composed,  as  this  anato- 
mist has  demonstrated,  of  two  very  different  substances, 
before  pointed  out  by  Winslow. 

1st.  It  is  almost  always  easy  to  trace  in  the  ganglions 
the  nervous  filaments  which  emanate  from  them  ; these 
filaments  preserve  in  them  their  cylindrical  form,  and 
white  colour,  and  are  easily  distinguished  from  the  non- 
medullary  substance,  in  which  they  are,  as  it  were,  buried. 
It  is  often  sufficient,  according  to  tbe  remark  of  Haase,  to 
cut  a ganglion  to  perceive  many  small  white  points,  which 
are  nothing  but  the  extremities  of  the  divided  nervous 
filaments.  These  filaments  frequently  anastomose.  In 
the  ganglions  situated  in  the  course  of  a single  nerve, 
their  direction  is  parallel  to  that  of  the  nerve  itself ; when, 
on  the  contrary,  many  nerves  unite  to  form  a ganglion, 
there  is  nothing  uniform  ; the  medullary  filaments  are 
seen  interlacing  in  all  directions,  and  thus  establishing 
numerous  communications  between  these  nerves.  Hence 
the  ganglions  of  the  first  species  are  elongated  and  usually 
oval,  whilst  those  of  the  second  have  a much  more  irreg- 
ular form. 


NERVOUS  SYSTEM  OF  ORGANIC  LIFE, 


71 


2d.  The  peculiar  substance  of  the  ganglions  is  soft, 
pulpy,  like  albumen  or  gelatine,  of  a reddish  grey,  some- 
times yellowish,  lodged  in  the  interstices  of  a very  deli- 
cate cellular  texture.  It  is  separated  with  more  or  less 
ease  from  the  nervous  filaments  which  it  surrounds  ; this 
separation  is  made  with  difiiculty  in  the  ganglions  of  the 
great  sympathetic  ; the  medullary  filaments  are  very  soft 
in  them  and  almost  semi-fluid  at  their  circumference,  so 
that  their  external  la3mrs  are  confounded  with  the  grey 
pulpy  matter  of  which  we  are  treating.  The  plexuses 
exhibit  nothing  similar  to  this  substance  ; it  is  this  which 
distinguishes  them  essentially  from  the  ganglions. 

It  has  been  thought  that  the  grey  substance  of  the 
ganglions  was  the  same  with  that  of  the  brain  ; that  the 
use  of  both  was  to  strengthen  the  w’hite  substance  of  the 
nervous  fibres.  If  we  examine  comparatively  a ganglion 
stripped  of  cellular  texture  and  a portion  of  brain  in  which 
the  grey  substance  predominates,  we  shall  see  that  this 
resemblance  does  not  exist.  Without  speaking  of  their 
dissimilar  appearance  or  of  the  phj'sical  characters  which 
distinguish  them,  the  manner  in  which  they  are  affected 
by  the  various  reagents  establishes  very  striking  diffei’- 
ences  between  these  two  textures.  This  is  a fact  already 
recognized  by  Bichat.  The  experiments  of  Wutzer  leave 
nothing  to  be  desired  upon  this  subject ; the  following  is 
an  extract  from  the  comparative  table  which  he  has  given 
of  the  chemical  properties  of  these  two  substances  in  his 
Treatise  de  Ganglioriim  Usu  et  Fabricd, 


72 


ADDITIONS  TO  THE 


Treated  with 
cold  concen- 
trated nitric 
acid, 


f The  one,  furnished  by  the  cervical  or  semilunar  gang- 
lions, taken  from  an  adult,  stripped  of  their  cellular  tex- 
ture and  washed  in  distilled  water,  experiences  the  fol- 
lowing phenomena  ; 1st,  it  undergoes  the  horny  harden- 
ing; 2d,  at  the  end  of  eight  days,  the  horny  hardening 
continues,  the  matter  blackens,  and  gives,  if  agitated, 
and  afterwards  left  to  deposit  a friable  precipitate,  in 
which  there  is  still  here  and  there  discovered  an  appear- 
ance of  structure  ; 3d,  at  the  end  of  a longer  time, 
putrefaction  renders  it  liquid,  but  it  exhales  no  other 
odour  than  that  of  the  acid. 

The  other,  taken  from  parts  of  the  cerebrum  or  cere- 
bellum formed  of  three  quarters  or  nearly  of  grey  sub- 
stance, 1st,  is  hardened  without  the  horny  hardening; 
2d,  diminishes  a little,  and  takes  the  consistence  of 
curd;  gives,  after  having  been  mixed  with  the  liquor  by 
agitation,  yellowish  albuminous  flakes  which  swim; 
3d,  the  odour  of  the  solution  has  something  similar  to 
^that  of  rancid  oil. 


By  the  same 
acid  boiling. 


f The  ganglion  is  dissolved  ; the  liquor  is  only  a little 

I turbid  ; by  cold  a slight  precipitate  is  formed  and  a 
small  quantity  of  the  matter  comes  to  the  surface, 

.1  The  cerebral  substance  is  dissolved  but  in  part,  a cer- 
tain quantity  swims  upon  the  liquor ; the  solution  pre- 
serves its  transparency  after  it  is  cold,  though  an  infinite 
i.nuraber  of  medullary  particles  is  seen  suspended  in  it. 


f The  first  is  softened  a little  ; its  white  filaments  dis- 
By  a solu-  j appear ; its  solution  is  slow  and  imperfect, 
tion  of  caustic -1  The  second  is  dissolved  more  easily  ; one  tenth  of 
potash  cold,  | the  matter  floats  upon  the  liquid,  and  does  not  mix 
I.wilh  it. 


("  In  one,  some  filaments  remain  insoluble  ; cooling  is 
By  a solu-  | followed  by  a deposition  formed  of  globules  of  a deep 
tion  of  boiling  J red. 

caustic  pot-]  In  the  other,  the  solution  is  almost  complete ; by 
ash,  j cooling,  the  surface  of  the  liquid  is  covered  with  flakes 

|_of  a yellowish  white. 


By  boiling 
alkohol. 


f The  substance  of  the  ganglion  is  contracted,  then 
I dissolved  to  two  thirds  ; the  liquor  is  turbid. 

< The  cerebral  matter  hardens,  and  afterwards  experi- 
[ cnees  changes  observed  by  M.  Vauquelin  ; albumen  is 
(^obtained  from  it. 


Finally,  different  reagents,  which  have  no  action  separately  on  the 
acid  solution  of  these  substances  give  precipitates  when  employed  to- 
gether ; the  alkaline  solution  presents  the  same  phenomenon,  when 
treated  with  the  muriatic  acid,  and  then  with  nut  galls.  These  pre- 
cipitates furnish  new  characters  by  the  differences  wdiich  they  exhibit  in 
their  properties,  according  as  they  belong  to  the  cerebral  substance  or 
to  that  of  the  ganglion. 


NERVOUS  SYSTEM  OF  ORGANIC  LIFE. 


73 


No  doubt  a good  analysis  of  the  ganglions  remains  to 
be  made,  in  order  to  know  precisely  the  difference  which 
exists  between  their  substance  and  that  of  the  brain,  but 
these  data  are  sufficient  to  prove  that  these  differences  are 
real. 

According  to  Scarpa,  the  peculiar  substance  of  the  gang- 
lions is  replaced  by  fat  in  very  fat  subjects  ; it  appears 
that  this  is  not  always  so.  When  the  corpulency  has 
been  the  greatest,  there  has  only  been  found  some  fatty 
vesicles  under  the  peculiar  membrane  of  the  ganglions 
(Wutzer).  We  can  conceive  that  if  fat  should  accumu- 
late there,  it  would  compress  the  grey  matter,  and  make 
it  disappear  in  whole  or  in  part. 


Uses  of  the  Ganglions. 

Page  273. — “ Scarpa  has  collected  the  opinions  of  all 
who  have  preceded  him,  together  with  his  own,  upon 
the  uses  of  the  ganglions.  I refer  to  what  he  has  said 
upon  this  subject.” 

We  can  divide  into  two  classes  the  opinions  of  physio- 
logists upon  the  uses  of  the  ganglions. 

Some  attribute  to  them  purely  mechanical  ones,  as  that 
of  facilitating  the  distrihution  of  the  nerves,  of  effecting 
the  intimate  mixture  of  the  nervous  filaments,  of  favour- 
ing their  union,  separation,  &c.  Meckel  the  elder,  Zinn, 
and  Scarpa  are  of  this  number. 

The  others  allow  them  functions  of  a higher  order, 
essentially  vital,  and  think  that  they  are  designed  to  mo- 
derate and  even  destroy  the  reciprocal  influence  of  the 
brain  and  the  nerves.  They  thus  explain  how  the  organs 
of  the  internal  life  are  to  a certain  extent  independent  of 
10 


74 


ADDITIONS  TO  THE 


the  cerebral  action,  and  how  the  brain  in  its  turn  per- 
ceives with  difficulty  the  impressions  made  upon  these 
organs  or  upon  their  nerves.  In  a word,  the  two  lives 
do  not  differ  more  than  in  their  nervous  systems. 

This  idea,  obscurely  stated  in  the  writings  of  Willis, 
F.  Petit  and  Bianchi  belongs  truly  to  Johnstone  ; most 
modern  physiologists  have  adopted  it.  It  must  be 
acknowledged  that  it  accords  very  well  with  what  we 
know  of  the  structure  of  the  ganglions,  and  nothing 
seems  more  capable  of  breaking  the  nervous  force  than 
these  medullary  interlacings  surrounded  by  a substance 
wholly  different  from  that  of  the  nerves.  It  is  asked 
nevertheless  why  some  impressions  are  transmitted  not- 
withstanding the  obstacle  which  the  ganglions  present  to 
them  ; why  the  vertebral  ganglions  do  not  perform  in 
respect  to  the  jaarts  which  receive  their  nerves  of  them, 
the  same  uses  as  the  ganglions  of  organic  life.  The  first 
objection  has  been  answered  by  saying,  that  the  ganglions 
are  imperfect  conductors,  that  they  insulate  sufficiently  to 
arrest  ordinary  impi-essions,  but  that  very  acute  ones  pass 
through  ^them.  Wutzer  has  seen  the  action  of  the  gal- 
vanic pile  upon  the  lumbar  ganglions  cause  very  severe 
pains,  accompanied  with  convulsive  motions,  whilst  a less 
degree  of  irritation  produced  nothing  similar.  As  to  the 
second  objection,  it  can  hardly  be  combatted  except  by 
considering  the  differences  of  structure  which  the  gang- 
lions of  the  spinal  nerves  exhibit  compared  with  those  of 
the  great  sympathetic,  differences  which  ought  to  produce 
a difference  in  the  functions. 

To  concentrate  the  nervous  power,  to  strengthen  it,  to 
spread  it  uniformly  upon  all  the  apparatus  of  organic  life 
and  thus  to  contribute  to  the  regularity  of  their  action, 
are  the  uses  commonly  attribute, d to  the  system  of  which 
we  are  treating.  It  is  difficult  to  assign  those  of  the 


NERVOUS  SYSTEM  OF  ORGANIC  LIFE. 


75 


w-anglions  which  are  found  in  the  posterior  branches  of  the 
nerves  of  the  spinal  marrow. 

Ganglions  of  Jinimals. 

Page  274. — “ If  the  ganglions  were  not  the  centres  of 
certain  important  functions  of  which  we  are  ignorant, 
would  they  be  so  invariable  in  the  animal  organization  ?” 

It  is  difficult  to  determine  to  what  part  of  the  nervous 
system  the  organs  of  this  kind  belong  which  are  met 
with  in  the  lowest  classes  of  animals.  Worms  and  in- 
sects have  insulated  swellings,  united  by  nervous  cords 
which  go  off  in  the  form  of  rays.  In  the  mollusca,  the 
whole  system  consists  of  two  great  nerves  twisted  around 
the  oesophagus  and  an  annular  swelling  which  embraces 
this  tube.  Blumenbach,  Cuvier,  Gall  and  J.  F.  Meckel 
admit  that  these  parts  correspond  with  the  spinal  marrow 
of  the  vertebral  animals.  If,  on  the  contrary,  Reil  and 
many  others  are  to  be  believed,  it  is  the  great  sympathe- 
tic that  they  represent.  Walter  of  Landshut,  assimilates 
the  nervous  cords  of  the  mollusca  to  the  nerves  of  the 
eighth  pair,  by  comparing  to  the  spinal  marrow  those  of 
insects  and  worms.  Weber  takes  the  ganglions  of  the 
vertebral  nerves  as  the  term  of  comparison.  But  no  one 
can  be  exact ; there  are  too  many  differences  of  structure, 
distribution  and  functions  between  these  imperfect  ner- 
vous systems  and  those  of  the  superior  animals.  What 
seems  to  approach  nearest  the  truth  is  the  term  of  com- 
parison adopted  by  Walter  for  the  nerves  of  the  mollusca, 
which  in  fact  very  much  resemble  the  nerves  of  the  eighth 
pair. 

For  the  same  reason,  we  can  hardly  give  the  name  of 
ganglions  to  those  swellings,  or  rather  to  those  irregular 


76 


ADDITIONS,  &c. 


masses,  whose  nature  is  still  but  little  known,  which  ap- 
pear to  take  the  place,  in  the  inferior  animals,  of  the  cen- 
tral organs  of  which  these  last  are  destitute.  It  is  how- 
ever upon  this  resemblance  that  is  founded  in  great  part 
the  opinion  of  those  who  pretend  that  the  brain  and  the 
spinal  marrow  are  assemblages  of  ganglions  ; the  proof  of 
it  is,  say  they,  that  these  ganglions  are  insulated  in  the  in- 
ferior animals.  We  shall  not  again  advert  to  this  opinion, 
which  is  contradicted  by  facts  already  stated  in  the  or- 
ganization, development,  &c.  of  the  nervous  system.  M. 
Serres  thinks,  like  Weber,  that  the  insulated  ganglions  of 
the  inferior  animals  answer  to  the  vertebral  ganglions. 

In  animals  who,  like  man,  have  the  spinal  marrow 
enclosed  in  a bony  canal,  the  system  of  the  ganglions  is 
not  by  any  means  developed  to  the  same  degrbe.  1st. 
Having  regard  to  the  whole  size  of  the  body,  this  system 
is  of  so  much  the  more  extent  as  the  animal  is  more 
elevated  in  the  scale  of  beings,  consequently  as  his  or- 
ganization is  more  perfect.  The  eighth  pair  diminishes  on 
the  contrary  in  the  same  proportion.  2d.  Its  develop- 
ment is  always  in  proportion  to  that  of  the  spinal  marrow 
if  we  compare  both  in  relation  to  the  whole  body  in 
general  and  not  to  the  brain  alone.  3d.  The  great  sym- 
pathetic follows  also  the  alimentary  canal  in  its  develop- 
ment. 4th.  Finally,  it  is  equally  connected  in  this  re- 
spect with  the  vascular  system. 


ADDITIONS 


TO  THE 

VASCULAR  SYSTEM  WITH  RED  BLOOD. 


Situation  of  the  Arteries. 

Page  292. — ‘‘  Both  of  them”  (the  trunks  and  branches 
of  the  arteries)  “ are  covered  almost  every  where  by  a 
thickness  of  parts  that  protects  them  from  external  in- 
jury.” 

Besides,  the  arteries  are  almost  every  where  situated  in 
the  direction  of  flexion  of  the  articulations.  Thus  the 
aorta  is  placed  in  nearly  it§  whole  course  in  front  of  the 
vertebral  column.  Thus  the  carotids  on  the  anterior  part 
of  the  neck,  the  iliacs  in  front  of  the  pelvis  and  the  sub- 
clavians  on  the  inside  of  the  shoulder,  all  occupy  the  side 
towards  which  the  motions  are  the  most  extended.  This 
becomes  more  evident  in  the  extremities.  We  see,  on 


78 


ADDITIONS  TO  THE 


the  inferior  ones,  the  crural  artery  at  first  situated  in 
front  of  the  ilio-femoral  articulation,  that  is  to  say,  in  the 
direction  of  the  flexion  of  this  articulation,  turning  within 
and  behind  to  its  inferior  part,  and  preserving  the  same 
relation  v/ith  the  articulation  of  the  knee.  The  foot  seems 
at  first  to  form  an  exception  ; but  this  exception  is  only 
in  appearance,  what  is  called  extension  in  this  part  being 
really  the  dii’ection  of  flexion,  if  we  compare  it  with  the 
hand,  and  is  besides  the  direction  of  the  most  extended 
motion.  Moreover,  it  is  in  descriptive  anatomy  that  we 
must  look  to  see  to  what  extent  every  thing,  in  the  neigh- 
bourhood of  an  artery,  unites  to  protect  it  efficaciously  from 
the  injuries  which  might  alter  its  structure.  The  arrange- 
ment of  which  we  are  treating  evidently  contributes  to 
this  object,  as  has  been  very  well  seen  by  Soemmering. 
Witbout  it  the  arteries  would  at  every  instant  be  exposed 
to  stretching,  which,  by  elongating  them  too  much,  would 
produce  the  double  inconvenience  of  embarrassing  the 
circulation  of  the  blood  in  their  interior,  and  of  producing 
in  their  texture,  which  is  but  slightly  extensible,  inevi- 
table ruptures.  This  situation  of  the  arteries  has  also 
another  advantage  ; it  follows  from  it  that  in  flexion,  they 
become  much  less  liable  to  external  injuries  ; which,  in 
various  places,  remedies  to  a certain  extent  their  super- 
ficial position. 

In  the  spaces  between  the  articulations,  the  arteries  of 
the  extremities  occupy  in  general  their  internal  side,  less 
exposed  than  the  others  to  the  action  of  external  powers, 
especially  when  the  limb  is  in  adduction. 

Termination  of  the  s.irteries. 

Page  301. — The  pilous,  epidermoid,  cartilaginous 
•systems,  &c.'  destitute  of  arteries,  contain  only  white 


VASCULAR  SYSTEM  WITH  RED  BLOOD, 


79 


fluids  in  the  division  of  the  general  capillary  system  that 
has  its  seat  in  them.” 

In  their  termination  in  difierent  organs,  the  arteries 
exhibit  also  many  points  for  consideration. 

1st,  The  course  they  run  before  arriving  at  it  is  longer 
or  shorter.  We  meet  in  this  respect  with  great  difier- 
ences,  which  themselves  are  not  uniform,  on  account  of 
the  varieties  of  origin  so  frequent  in  this  system.  In 
general  the  arteries  arise  at  a little  distance  from  the 
organ  to  which  they  are  destined.  When  a contrary 
arrangement  exists,  it  arises  from  some  local  cause.  It  is 
thus  that  the  spermatic  arteries  are,  at  their  origin,  very 
far  from  the  testicles,  because  the  testicles  were  originally 
situated  much  higher  up. 

2d.  The  mode  of  distribution  of  the  arteries,  their 
number  and  size  vary  in  each  organ.  There  are  some 
which  possess  many  arteries  ; this  is  the  case  even  with 
the  greatest  number.  Others,  as  the  liver,  the  kidneys, 
the  spleen,  &c.  receive  but  a single  trunk.  The  arteries 
are  almost  always  more  or  less  divided  before  penetrating 
the  substance  of  the  organs,  as  we  see  in  the  brain,  the 
bones,  the  muscles,  &c.  Sometimes  they  enter  them  on 
one  side  only,  and  occupy  but  a very  small  space  on  their 
surface  ; sometimes  almost  the  whole  circumference  of 
the  organ  gives  passage  to  them.  Finally,  their  size 
difiers  in  the  different  organs  j it  is  generally  in  relation 
with  the  nature  of  the  functions  which  they  perform. 

3d.  The  arteries,  when  arrived  in  the  textures  them- 
selves, give  rise,  by  their  divisions  and  subdivisions,  to 
very  delicate  networks.  The  form  of  these  networks  is 
not  the  same  every  where  ; Prochaska  and  Soemmering 
have  pointed  it  out  for  a great  number  of  parts.  They 
are  trees  in  the  intestine,  stars  in  the  liver,  tufts  in  the 


80 


ADDITIONS  TO  THE 


tongue,  &c.  ; so  that  we  can  by  the  aid  of  a microscope, 
at  a single  glance,  as  it  were,  determine  whence  the  ves- 
sels come  that  are  previously  injected. 

Resistance  of  the  Jirteries. 

Page  306. — “ This  longitudinal  resistance”  (of  the  ar- 
teries) “ to  distension  is  less  than  the  lateral  resistance  op- 
posed to  the  injection  ; experiments  prove  it,  and  it  arises 
without  doubt  from  this,  that  no  fibre,  in  the  first  case, 
is  found  directly  opposed  to  the  efibrt.” 

The  cellular  coat  is  in  fact  almost  the  only  one  capable 
of  sustaining  an  effort  which  is  exerted  in  the  longitudi- 
nal direction,  whilst  the  peculiar  coat  resists  with  it  when 
the  effort  is  lateral.  Besides,  the  resistance  of  the  arteries 
is  not  the  same  in  all ; it  depends  in  general  on  the  thick- 
ness of  their  parietes ; the  cerebral  arteries,  which  have 
such  delicate  ones,  are  so  much  the  weaker  than  other 
arteries  of  the  same  size.  For  the  same  reason,  the 
trunks  have  more  resistance  than  the  branches,  these  than 
the  smaller  branches,  &c  ; only  as  the  thickness  does  not 
diminish  in  the  ratio  of  the  capacity,  it  follows  that  the 
arteries  the  most  distant  from  the  part,  are,  in  relation 
to  their  caliber,  the  most  resisting.  Another  cause,  ac- 
cording to  Clifton-Wintringham,  which  makes  the  small 
arteries  resist  more,  is  that  their  texture  is  softer  and 
looser. 

But  few  comparative  experiments  have  been  made  upon 
the  strength  of  the  arterial  parietes  in  the  longitudinal 
direction.  The  object  of  those  of  Wintringham  was  to 
ascertain  the  lateral  resistance  ; it  appeared  to  him  to  be 
greater,  in  relation  to  the  thickness  even  of  the  parietes, 
in  the  small  arteries  than  in  the  large  ones.  The  aorta 


VASCULAR  SYSTEM  WITH  RED  BLOOD. 


81 


has  also  borne  a greater  effort  at  its  inferior  extremity 
than  near  its  origin.  Gordon  has  endeavoured  to  measure 
the  effects  of  the  distension  ; he  has  ascertained  that  it 
requires  a greater  weight  to  rupture  the  external  iliac, 
than  the  carotid.  But  in  his  experiments,  the  rupture 
took  place  where  the  suspensory  cord  was  attached  ; 
there  was  at  the  same  time  a section  of  the  artery ; 
so  that  nothing  can  be  concluded  from  it  in  relation 
to  pure  and  simple  distension.  If  we  should  wish  to 
repeat  these  experiment,  which,  however,  do  not  appear 
to  lead  to  any  very  important  result,  we  might  insulate 
the  artery  of  a limb  for  a certain  extent  without  entirely 
separating  it,  and  afterwards  employ  upon  this  dis- 
articulated limb  all  the  necessary  efforts.  We  should 
avoid  in  this  way  the  inconvenience  of  ligatures. 

In  the  arterial  curvatures,  the  convex  side  is  thicker 
and  stronger  than  the  concave  one.  This  arrangement, 
no  douht  accommodated  to  the^  greater  effort  of  the 
blood  on  that  side,  is  very  evident  at  the  arch  of  the 
aorta. 

Nature  of  the  Middle  Coat  of  the  Jirteries. 

Page  308. — ‘‘  The  action  of  different  reagents  upon 
the  arterial  texture,  proves  clearly  how  much  it  differs 
from  the  muscular.  There  are  then  general  phenomena 
common  to  all  the  solids  ; but  different  peculiar  phe- 
nomena that  are  distinctive.” 

Those  who  consider  the  peculiar  membrane  of  the 
arteries  as  of  a muscular  nature,  and  Haller,  Walter  and 
Soemmering  are  of  this  number,  think  so,  1st,  because 
its  fibres  become  soft  and  greyish  in  the  small  ai’teries, 
and  resemble  very  much,  at  least  in  appearance,  those  of 
11 


82 


ADDITIONS  TO  THE 


the  intestine,  bladder,  &c.  ; 2d,  because  the  same  appear- 
ance is  found  in  animals  ; 3d,  because,  notwithstanding 
the  dryness,  resistance,  elasticity  and  species  of  brittleness, 
which  distinguish  the  arterial  fibre,  there  is  not  more 
difference  between  this  fibre  and  the  muscular,  than  is 
found  between  the  different  kinds  of  muscles  ; between 
the  great  pectoral  of  birds  and  the  muscles  of  their 
claws  or  stomach,  for  example ; 4th,  finally,  because 
the  properties  which  the  arteries  enjoy  during  life  also 
approximate  their  texture  to  the  muscular.  It  might 
be  added,  that  it  is  not  very  dissimilar  in  chemical 
properties  ; for  I am  confident  it  contains  a certain 
quantity  of  fibrin. 

These  considerations  nevertheless  do  not  seem  to  me 
o be  sufficient  to  warrant  us  in  ranking  the  arterial 
texture  among  those  which  have  the  muscular  fibre 
essentially  for  their  base.  I think  rather,  considering 
the  elasticity  which  ffrras  the  principal  character  of  it, 
that  this  texture  belongs,  as  some  anatonnists  have  already 
thought,  to  the  yellow  or  elastic  fibrous  system  which 
will  be  examined  hereafter. 

Cellular  Membrane  and  Sheath  of  the  dirteries. 

Page  318. — “ The  arteries  have  around  them  two 
kinds  of  cellular  texture  ; one,  which  is  very  external, 
loose,  fatty,  full  of  serum,  with  distinct  layers,  unites 
them  to  the  neighbouring  parts  ; the  other,  firm,  com- 
pact, not  fatty,  filamentous  and  not  lamellated,  forms 
the  first  of  their  coats.” 

This  cellular  coat,  {cellulosa  propria  of  Haller)  re- 
jected by  Monro,  Walter,  Scarpa  and  Mascagni,  and 
which  Soemmering  united  to  the  peculiar  membrane,  is 


VASCULAR  SYSTEM  AYITH  RED  BLOOD. 


S3 


not  less  distinct  from  the  other  coats  which  it  covers, 
than  from  the  cellular  texture  which  surrounds  it. 

It  is  a fibro-cellular  membrane,  delicate,  tolerably 
dense  however,  and  really  forming  a constituent  part 
of  the  arterial  tube.  In  the  great  arteries  it  is  divided 
into  two  laminae ; one  external,  which  approximates 
more  to  cellular  texture  ; the  other  internal,  yellowish 
and  tough,  which  resembles  the  layers  of  the  middle 
coat.  Its  appearance  upon  the  arteries  of  the  middle 
size  is  that  of  the  aponeuroses,  or  still  more  of  the  neu- 
rilema.  Its  texture  is  composed  of  fibres  interlaced  and 
oblique,  more  separated  without  than  within  ; these 
fibres  are  especially  apparent  in  the  distension  of  the 
artery,  either  lengthwise,  or  across,  because  they  stretch 
and  separate  before  breaking.  Mascagni  has  given  a 
good  plate  of  them.  The  small  arteries  have  this  coat 
thicker  than  the  large  ones,  in  proportion  to  their  size  ; 
it  is  on  this  account  that  they  bear  ligatures  better, 
which,  as  is  known,  only  act  upon  the  cellular  coat. 

Into  this  membrane  are  inserted  many  soft  and  exten- 
sible filaments,  which  come  from  a species  of  sheath 
wdiich  the  artery  receives  from  the  surrounding  cellular 
texture.  It  is  the  only  relation  which  there  is  between 
it  and  this  cellular  texture.  By  means  of  this  arrange- 
ment, the  artery  slides  easily  in  the  interior  of  its  cellu- 
lar canal ; the  retraction  of  divided  arteries  is  very  much 
favoured  by  it. 

The  cellular  sheath  of  the  arteries,  the  external  coat 
of  Soemmering,  described  by  Haller  under  the  name  of 
tunica  cellulosa  adscititia,  is  in  fact  nothing  but  this 
lamellated  cellular  texture  which  joins  and  embraces  them 
so  as  to  form  a real  canal  around  them.  Hebenstreit  has 
treated  of  it  in  a dissertation  which  forms  a part  of  the 
Collection  of  Dissertations  of  Haller.  This  sheath  is 


84 


ADDITIONS  TO  THE 


attached  on  one  side  to  the  external  membrane  by  the 
elongations  of  which  we  have  just  spoken,  and  is  con- 
tinued on  the  other  with  the  cellular  system.  It  is 
wanting  in  some  arteries  which  have  serous  coverings. 
Others  are  destitute  of  it,  from  the  want  of  cellular  tex- 
ture in  the  parts  where  they  are  found.  Its  arrangement 
varies  like  that  of  this  texture  ; in  general  compact  on 
the  extremities,  it  is  very  loose  in  some  parts,  around 
the  spermatic  arteries  for  example.  These  differences 
deserve  an  examination,  because  they  may  explain  various 
morbid  phenomena.  Thus  arterial  ruptures  are  followed 
in  the  brain  by  a general  effusion  which  disorganizes  its 
substance,  whilst  in  the  extremities  the  cellular  sheath 
prevents  this  accident  by  circumscribing  the  progress  of 
the  effusion  ; thus,  in  this  last  case,  the  blood  infiltrates 
to  a greater  or  less  extent  according  to  the  resistance 
wdiich  the  sheath  opposes  to  it,  &c. 

Nerves  of  the  Jlrteries. 

Page  322. — There  is  merely  juxta-position”  (between 
the  cerebral  nerves  and  the  arteries)  “ as  we  see  it  in  the 
extremities,  in  the  intercostal  spaces,  &c.” 

The  nerves  of  the  arteries  are  so  much  the  more  abun- 
dant in  proportion  as  these  vessels  are  of  a less  caliber ; 
they  are  more  evident  upon  the  branches  than  the  trunks. 
Those  of  the  arteries  of  the  extremities  come  in  part  from 
the  cerebral  nerves.  Lucae  says  that  he  has  traced  them 
into  the  arteries.  He  has  made  two  classes  of  them  in 
relation  to  their  course ; 1st,  some  stop  in  the  cellular 
coat  and  are  lost  there,  after  having  run  some  time  in  the 
cellular  texture  which  surrounds  it  ; 2d,  others  pass 
through  this  coat  and  go  to  the  peculiar  membrane,  upon 


VASCULAR  SYSTEM  WITH  RED  BLOOD. 


85 


which  they  are  spread  into  a very  delicate  network.  The 
first  are  short  and  flattened ; the  second,  which  are  ex- 
tremely delicate,  have  a little  more  consistence,  their  form 
is  rounder  and  they  run  a shorter  course.  No  one  reaches 
the  internal  membrane  ; Oudemann  says  however  that  he 
has  traced  them  to  the  nervous  membrane  of  Haller.  Some 
arteries  appear  to  be  destitute  of  nerves.  The  pulmonary 
tree  receives  fewer  of  them  than  the  aortic.  According  to 
Lucae,  the  nerves  of  the  arteries  are  less  apparent  in  old 
age,  particularly  the  filaments  destined  for  the  middle  coat. 

Irritability  of  the  Arterial  Texture. 

Page  332. — “ The  contraction  produced  by  the  defect 
of  extension,  is  that  which  characterizes  the  contractili- 
ty of  texture.  Irritability  or  sensible  organic  contrac- 
tility, on  the  contrary,  uniformly  supposes  the  applica- 
tion of  a stimulus.” 

Notwithstanding  all  these  considerations,  there  are  phy- 
siologists, who  allow  to  the  arterial  texture  the  faculty  of 
contracting  under  the  influence  of  an  appropriate  stimulus. 
The  reasons  which  they  allege  in  favour  of  tliis  opinion 
are  the  following.  1st.  If  the  arteries,  say  they,  do  not 
always  contract  in  experiments,  they  resemble  in  this  res- 
pect some  textures  of  whose  irritability  there  is  no  doubt. 
The  intestines,  the  bladder  and  the  stomach  sometimes 
give  no  sign  of  irritability.  2d.  The  action  of  the  acids, 
which  Bichat  considers  as  a mere  horny  hardening,  is  dif- 
ferent during  life  and  after  death  ; in  the  first  case,  there 
is  a real  contraction  ; in  the  second,  it  is  rather  a kind  of 
erosion,  as  Verschuir  has  seen.  3d.  The  same  author  has 
succeeded  in  producing  a contraction  of  the  artery,  by 
merely  irritating  it  with  a scalpel.  4th.  In  other  experi^ 


Stt 


AUDITIONS  TO  THE 


ments,  the  simple  contact  of  the  air  has  produced  a sudden 
and  very  evident  contraction,  sufficient  to  efface  almost 
entirely  the  cavity  of  the  artery.  5th.  This  contraction, 
in  all  these  cases,  extended  beyond  the  point  touched  ; it 
ceased  when  the  stimulus  was  remo'Ved.  6th.  The  elec- 
tric spark  has  also  produced  contractions  according  to 
Bikker  and  Van-den-Bos.  7th.  It  is  even  said  that  this 
effect  has  been  obtained  by  applying  stimuli  to  the  nerves 
of  the  arteries.  Galvanism  has  been  successfully  employ- 
ed in  this  way  by  Giulio  and  Rossi.  Home  employed 
alkalies ; their  contact  with  the  great  sympathetic  nerve 
produced  violent  pulsations  in  the  carotid  artery.  He 
was  led  to  this  experiment  by  the  local  changes  which 
the  circulation  appeared  lo  experience  from  severe  pains 
from  an  ulcer.  8th.  Thomson  has  seen  the  arterial 
parietes  contracted  by  the  action  of  ammoniac,  so  that  its 
cavity  seemed  to  have  entirely  disappeared.  The  muriate 
of  soda,  on  the  contrary,  almost  uniformly  dilates  them. 
Many  of  these  experiments  require,  no  doubt,  to  be 
repeated ; but  we  cannot  deny,  that  the  contraction  of  the 
arteries  may  be  very  different  during  life  from  what  it 
is  after  death;  for,  1st,  an  artery,  opened  between  two 
ligatures,  does  not  continue  to  empty  itself  some  instants 
after  death,  except  from  an  excess  of  distension,  its  elas- 
ticity does  not  make  it  contract.  2d.  Arteries,  empty  at 
the  moment  of  death,  and  being  still  contracted  in  virtue  of 
this  contraction,  return  to  their  ordinary  dimensions  when 
all  vital  influence  has  entirely  ceased ; their  elasticity, 
which  resumes  its  ascendancy,  then  supports  their  parietes 
separate ; this  is  what  is  seen  especially  in  death,  from 
hemorrhage  ; 3d,  so  in  the  experiments  cited  above, 
the  contraction  ceased  after  death,  and  that  which 
was  obtained  by  putting  the  elasticity  in  action  by 
the  distension  of  the  parietes  was  much  less  marked.  No 


VASCULAR  SYSTEM  WITH  RED  BLOOD. 


87 


doubt  that  the  force  which  thus  makes  the  arteries  con- 
tract during  life  does  not  differ  from  that  which  presides 
over  the  contraction  of  the  heart,  the  intestines,  &c.  ; 
perhaps  it  is  wrong  to  give  it  the  name  of  irritability  ; 
but  that  of  contractility  of  texture  is  no  more  suitable 
to  it.  Kramp  has  proposed  to  make  a particular  force  of 
it  which  he  calls  the  vital  force  of  the  arteries.  Parry 
refers  all  its  effects  to  tone  or  insensible  organic  contrac- 
tility. Whatever  be  itsnature,  its  intensity  increases  as  the 
arteries  become  smaller,  which  Soemmering  attributes 
to  the  greater  quantity  of  nerves  which  the  small  ones 
receive ; the  elasticity  diminishes  in  the  same  proportion. 

Action  of  the  Arteries  in  the  Circulation. 

Page  345. — ‘‘  It  is  not  the  contraction  of  the  arteries 

that  drives  the  blood  to  their  extremities. Each  jet  of 

the  arterial  throw  should  correspond  to  each  relaxation  of 
the  ventricle  ; the  contrary  of  this  is  the  case  as  I have 
just  said.” 

If  the  arteries  do  not  contract  upon  the  blood,  the  flow 
of  this  fluid  would  not  be  continuous  but  intermittent ; 
whilst  it  is,  as  it  were,  remittent.  The  jet  of  an  open 
artery  is  increased  at  each  contraction  of  the  ventricle, 
because  this  contraction  increases  the  velocity  of  the  cir- 
culation. It  is  diminished  in  the  relaxation  because  there 
is  then  only  the  arterial  action  Avhich  makes  the  blood 
flow.  The  jet  should  cease  entirely  at  each  relaxation  of 
the  ventricle,  if  it  was  only  owing  to  the  contraction  of 
this  last.  There  are  then  two  causes  of  the  motion  of  the 
blood.  1st.  The  arteries,  always  full,  constantly  tend,  by 
their  elasticity  and  contractility  to  react  upon  this  fluid. 
2d.  The  contraction  of  the  heart  is  added  to  this  by  in- 


88 


ADDITIONS  TO  THE 


tervals,  and  gives  to  the  motion  a new  activity.  This 
last  cause  is  much  the  most  important,  especially  in  the 
great  arteries,  but  the  first  is  nevertheless  real. 

Development  of  the  Vascular  System. 

Page  364. — “ The  arteries  are  made  to  develop  them* 
selves,  and  the  heart  does  not  hollow  them  out,  as  Haller 
has  said,  in  the  interior  of  our  organs  by  the  force  of  its 
impulse.  This  mechanical  manner  of  considering  their 
formation  is  evidently  contrary  to  the  known  laws  of  the 
animal  economy.” 

The  opinion  of  Haller  is  so  much  the  less  admissible, 
as  it  appears  that  there  are  vessels  before  the  heart  exists. 
The  development  of  these  vessels,  and  in  general  of  the 
whole  vascular  system,  is  a point  still  obscure,  but  never- 
theless curious.  Malpighi,  Haller,  Wolff,  and  especially 
in  recent  times  Pander,  have  traced  it  in  the  chick.  The 
first  vessels  appear  in  the  membrane  of  the  yolk,  which 
represents  the  umbilical  vesicle  of  man  and  the  superior 
animals.  The  vein  of  this  part  appears  before  any  of  the 
rest  of  the  vascular  system.  Its  ramifications  commence 
by  small  insulated  cavities,  species  of  vesicles,  which  are 
afterwards  united  by  grooves.  They  are  at  first  mere 
hollowed  passages  in  the  membrane  of  the  yolk,  filled 
with  a colourless  fluid ; the  blood  afterwards  shows  its 
colour  in  them,  the  parietes  become  moi’e  distinct  and  their 
consistence  greater.  The  small  branches,  branches  and 
trunk  of  the  vein  are  developed  in  the  same  manner.  The 
vena  porta  succeeds  to  that  of  the  vesicle,  of  which  it 
appears  to  he  but  a continuation.  Soon  after  this  vein  is 
enlarged  at  its  superior  extremity  to  give  origin  to  the 
heart.  This  is  then  semicircular,  and  formed  entirely  by 


VASCULAR  SYSTEM  WITH  RED  BLOOD. 


89 


the  left  ventricle.  The  origin  of  the  aorta  is  afterwards 
joined  to  it  and  then  the  auricle ; both  at  first  quite  dis- 
tinct from  the  ventricle,  gradually  approximate  it.  The 
space  which  thus  exists  for  some  time  between  this  last 
and  the  auricle,  is  the  auricular  canal.  From  the  aorta 
arise  successively  all  the  other  arteries,  beginning  with 
that  of  the  yolk  or  vesicle,  which  the  vessels  of  the 
allantoid  membrane  soon  follow  ; the  development  of  the 
arteries  is  followed  by  that  of  the  corresponding  veins. 
On  the  other  hand,  the  liver  is  developed  and  the  vena 
porta,  united  to  the  umbilicus,  is  almost  exclusively  dis- 
tributed there  ; the  portion  of  this  vein  which  is  extended 
beyond  forms  the  ductus  venosus.  The  cavities  of  the 
heart  are  completed  ; a partition  divides  the  auricle  into 
two  parts,  which  still  communicate  by  a large  opening  ; 
there  arises  from  the  superior  part  of  the  left  ventricle  a 
small  tubercle,  which  by  extending  towards  the  apex  of  the 
heart,  gives  origin  to  the  right  ventricle.  At  this  period, 
the  base  of  the  heart  which  the  left  side  alone  forms,  estab- 
lishes a communication  between  the  two  ventricles,  which 
makes  the  aorta  seem  to  arise  from  both  of  them  ; the 
pulmonary  artery  is  yet  only  indicated  by  a bifurcation 
which  the  aorta  exhibits  a little  above  its  origin  ; the  two 
branches  which  result  from  this  bifurcation  unite  again 
after  a short  course.  In  the  ulterior  development  of  the 
heart,  the  place  of  their  separation  is  found  more  and 
more  approximating  this  origin  ; the  two  divisions  finally 
detach  themselves  entirely,  and  the  pulmonary  artery 
becomes  a trunk  insulated  at  its  origin,  and  forming  as  it 
were  a second  branch  to  the  aorta.  It  is  itself  divided 
for  the  lungs  of  each  side,  and  takes  beyond  the  name  of 
ductus  arteriosus. 

By  admitting  that  these  phenomena,  observed  in  the 
oviparous  animals,  take  place  also  in  man,  as  some  facts 
12 


90 


ADDITIONS  TO  THE 


seem  to  prove,  we  see,  1st,  that  in  the  beginning  the 
circulating  organs  are  much  less  numerous  than  they  are 
to  be  afterwards.  The  heart  has  but  one  ventricle  and 
one  auricle ; the  vena  porta  is  the  only  venous  trunk,  the 
aorta  the  only  artery,  &c.  The  motion  of  the  blood  must 
then  be  very  simple  at  this  period  ; this  is  also  what  is 
observed  in  the  chick.  The  blood,  in  this  last,  runs  a very 
simple  course  at  the  commencement  ; it  is  a single  circle, 
formed  by  the  vein  of  the  yolk,  the  vena  porta,  which  is  a 
continuation  of  it,  the  heart,  the  aorta  and  the  artery  of 
the  yolk.  There  must  be  added  to  it  afterwards  the  um- 
bilical vessels,  whose  dev'elopment  follows  nearly  that 
of  the  vessels  of  the  vesicle  ; this  gives  a little  more  extent 
to  the  circulation  without  rendering  it  much  more  com- 
plicated. 2d.  In  a second  period,  on  the  contrary,  the 
circulatory  organs  are  more  numerous  than  after  birth. 
Thus  the  ductus  arteriosus,  the  ductus  venosus,  the  um- 
bilical arteries  and  vein  and  the  foramen  ovale  are  after- 
wards to  disappear.  There  however  remain  traces  of  the 
simplicity  of  the  first  period  ; the  auricles,  though  two  in 
number,  communicate  together ; the  course  of  the  blood 
is  much  more  complex,  but  the  two  circulations  are  still 
in  part  confounded.  It  is  not  until  this  second  period 
that  the  circulation  begins  to  be  well  understood  in  man. 


MORBID  ANATOMY  OP  THE  VASCULAR  SYSTEM  WITH 
RED  BLOOD. 

I.  Alterations  in  the  External  Forms. 

The  arteries  often  increase  in  size,  either  in  their 
whole  extent,  or  in  a single  point,  or  even  on  one  side 
only  of  their  circumference.  The  increase  of  the  arteries 


VASCULAR  SYSTEM  WITH  RED  BLOOD. 


91 


in  their  whole  length  is  a real  hypertrophy,  which  takes 
place  when  the  organs  themselves  are  the  seat  of  an 
excess  of  nutrition,  when  they  experience  a very  acute 
and  long  continued  irritation,  and  under  various  circum- 
stances pointed  out  above;  After  the  obliteration  of  an 
artery,  the  collateral  branches  do  not  increase  in  breadth 
only,  but  in  length  also  ; thus  they  describe  curves  which 
did  not  before  exist.  The  partial  dilatation  constitutes 
one  of  the  varieties  of  aneurism,  the  true  aneurism  of  the 
ancients.  This  affection  is  in  fact  in  the  beginning  only 
a simple,  circumscribed  and  sac-like  dilatation  of  the  three 
arterial  coats,  as  is  proved  by  many  observations  ; the 
artery  is  rarely  dilated  uniformly  and  in  its  whole  cir- 
cumference ; when  this  takes  place  the  disease  exhibits 
differences  sufficiently  striking  to  warrant  us  in  distin- 
guishing it,  as  Scarpa  has  done,  from  aneurism;  these 
two  kinds  of  dilatation  are  sometimes  united. 

The  contraction  of  the  arteries  is  less  common  than 
their  dilatation.  1st.  It  is  observed  whenever  the  blood 
ceases  to  pass  through  them,  or  does  it  in  less  quantity,  as 
happens  in  gangrene,  especially  in  that  variety  known 
under  the  name  of  dry  gangrene,  in  some  cases  of  atro- 
phy, paralysis,  &c.  2d.  Circumscribed  contractions,  the 

cause  of  which  it  is  very  difficult  to  determine,  have  been 
met  with,  particulai'ly  in  the  great  arteries,  such  as  the 
aorta  and  the  pulmonary  artery.  In  the  greatest  number 
of  cases  the  texture  of  the  artery  is  however  sound  ; some- 
times it  has  been  found  thickened.  There  is  often  con- 
nected with  this  alteration  some  organic  disease  of  the 
heart,  or  even  the  rupture  of  this  oi'gan.  3d.  Various 
tumours,  situated  in  the  course  of  the  arteries  may  also, 
by  the  pressure  they  exert,  diminish  their  caliber  more 
or  less.  Old  aneurismal  tumours  produce  this  effect  upon 
the  arteries  in  which  they  are  situated,  and  upon  the 


92 


ADDITIONS  TO  THE 


branches  they  are  near  and  which  they  compress.  Under 
almost  all  these  circumstances,  the  contraction  of  the  ar- 
teries may  extend  even  to  their  obliteration. 

The  manner  of  distribution  of  the  arteries  undergoes 
important  changes  when  a principal  trunk  is  obliterated 
in  a part;  there  is  then  formed  one  or  more  anastomosing 
passages  which  supply  the  place  of  the  trunk  in  the 
whole  course  of  its  obliteration,  and  which  carry  the 
blood  from  the  last  branch  furnished  above  the  obliterated 
trunk,  to  the  first  furnished  below  it.  This  is  what  is  seen 
in  ligature  of  an  artery,  after  wounds  of  these  vessels, 
aneurisms,  &c. 

II.  Alterations  in  the  Organization. 

The  internal  membrane  is  much  more  susceptible  than 
the  others  to  inflammation.  Sometimes  this  state  is  first 
developed  in  this  membrane,  sometimes  it  is  transmitted 
to  it  from  other  organs  ; it  is  thus  that  in  acute  inflam- 
mation of  the  thorax  or  abdomen,  the  internal  membrane 
of  the  aorta  has  sometimes  been  at  the  same  time  found 
greatly  inflamed  ; in  the  afiected  parts  themselves,  the 
arteries  commonly  partake  of  the  inflammation  of  the 
other  textures.  The  redness  which  characterizes  this 
arterial  phlegmasia  is  usually  accompanied  by  a thicken- 
ing of  the  membrane  and  an  effusion  of  an  albuminous 
nature,  sometimes  very  copious  ; the  vessels  of  the  pecu- 
liar membrane  are  also  frequently  more  or  less  engorged. 

Inflammation  of  the  arteries  is  followed  by  their  oblitera- 
tion, when  the  two  sides  of  the  inflamed  internal  mem- 
brane unite  together.  This  adhesion  is  owing,  like  most 
of  the  phenomena  of  this  kind,  to  the  circumstance  that 
the  effused  fluid  passes  to  the  solid  state  and  forms  a sort 
of  false  membrane  which  afterwards  becomes  organized. 


VASCULAR  SYSTEM  WITH  RED  BLOOD. 


93 


It  is  in  this  way  that  we  can  understand  how,  notwith- 
standing the  destruction  of  the  arteries  in  ulcers  often- 
times very  extensive,  no  hemorrhage  takes  place  ; the 
preceding  inflammation  has  first  obliterated  the  vessels. 
Pus  has  never  been  found  in  the  arteries ; perhaps  it  is 
carried  off  by  the  blood,  as  fast  as  it  is  formed.  Ought 
we  to  refer  to  a state  of  induration  or  of  chronic  inflam- 
mation many  of  the  organic  diseases  of  the  arteries,  which 
are  accompanied  by  a greater  thickness  and  consistence  of 
their  texture?  This  question  cannot  be  resolved.  What 
is  certain  is,  that  inflammation,  connected  cither  inciden- 
tally, or  as  effect  or  cause,  is  often  united  to  similar  altera- 
tions. Gangrene  never  succeeds  to  the  inflammation  of 
the  internal  membrane  alone ; but  the  arteries  are  often 
comprehended  in  eschars  ; it  happens  then,  that  the  blood 
is  coagulated  beyond  the  dead  portion,  so  that  there  is  no 
hemori'hage  when  the  eschar  separates,  unless  the  vessel 
be  very  large. 

The  cellular  texture  exterior  to  the  arteries  is  subject 
to  the  same  alterations  as  the  rest  of  the  cellular  system  ; 
inflammation  may  engorge,  thicken  and  ulcerate  it,  suppu- 
ration may  destroy  it,  &c.  The  cellular  coat,  properly  so 
called,  is  but  very  rarely  inflamed.  When  it  happens  and 
the  inflammation  is  long  continued,  there  sometimes 
results  from  it  that  sort  of  brittleness  which  has  been 
treated  of  in  the  article  on  the  cellular  system  ; a brittle- 
ness which  has  perhaps,  however,  been  much  exaggerated. 

That  state  of  the  arteries  of  which  Bichat  has  spoken 
and  which  resembles  their  inflammation,  because  it  con- 
sists in  a more  or  less  extensive  redness  of  their  internal 
membrane,  has  been  met  with  in  cases  in  which  it  could 
be  attributed  neither  to  maceration,  exposure  to  the  air, 
the'presence  of  a coagulum  nor  to  the  time  that  had 
elapsed  since  death.  (See  Hodgson  on  the  diseases  of  the 


94 


ADDITIONS  TO  THE 


arteries.)  We  know  not  then  if  it  be  not,  under  some 
circumstances,  a real  morbid  alteration.  Accordinsr  to 
Franck,  this  redness  was  constant  and  occupied  the  whole 
extent  of  the  arterial  S3'stem  in  a species  which  he  had 
occasion  to  observe. 

The  solutions  of  continuity  of  the  arteries  difier,  accord- 
ing as  thej’’  penetrate  the  cavity  of  the  vessel,  or  affect 
only  a part  of  its  membranes. 

The  first  case,  which  is  the  most  common,  has  been 
very  well  observed  by  Dr.  Jones  upon  dogs.  I have  also 
made  some  experiments  upon  this  subject.  The  follow- 
ing is  what  takes  place  when  an  artery  of  a living  animal 
is  opened. 

1st.  If  it  be  by  a simple  puncture,  with  the  point  of  a 
needle  for  example,  a small  quantity  of  blood  flows,  a 
coagulum  is  formed  in  the  cellular  sheath  and  stops  the 
hemorrhage.  This  coagulum  afterwards  disappears,  the 
edges  of  the  opening  inflame,  and  adhesion  takes  place. 
The  cicatrix  is  confounded  in  time  with  the  arterial  tex- 
ture, and  no  traces  are  left  of  the  small  wound.  The 
cavity  of  the  artery  is  preserved. 

2d.  When  the  wound  is  of  some  extent,  the  issue  is 
different  according  to  the  state  of  the  cellular  sheath  and 
the  direction  and  size  of  the  opening.  If  the  sheath  has 
been  destroyed,  the  hemorrhage  continues  in  all  cases; 
and,  though  suspended  for  a time  by  syncope,  it  only 
ceases  with  the  life  of  the  animal.  When,  on  the  con- 
trary, the  sheath  remains  uninjured,  1st,  if  the  wound  be 
longitudinal,  to  the  jet  of  blood  which  escapes,  succeeds 
the  formation  of  a clot  which  shuts  the  opening ; then  this 
cicatrizes,  as  in  the  case  of  simple  puncture  ; only  the 
cicatrix  remains  apparent  ; it  is  linear,  continuous  with 
the  texture  of  the  artery,  and  is  seen  very  well  by  open- 
ing this  last  and  examining  its  parietes  against  the  light; 


VASCULAR  SYSTEM  WITH  RED  BLOOD. 


95 


2d,  if  the  wound  be  transverse,  but  occupying  only  a quar- 
ter of  the  circumference  of  the  artery,  the  hemorrhage, 
though  more  abundant  than  in  the  preceding  case,  because 
the  retraction  of  the  arterial  fibres  gives  a circular  form 
to  the  opening,  may  still  stop  of  itself,  and  its  suspension 
be  followed  by  the  formation  of  a cicatrix,  of  which  I 
have  preserved  examples  ; 3d,  if  the  wound  embraces 
half  the  circumference  of  the  artery,  the  opening  takes  an 
elliptical  form,  and  death  necessarily  ensues  ; 4th,  finally, 
if  three  quarters  of  the  circumference  of  the  artery 
have  been  divided,  the  separation  is  very  considerable ; 
the  opposite  ends  of  the  artery,  extremely  elongated, 
represent,  if  we  may  so  say,  the  extremities  of  two  pens 
united  at  their  points  ; the  kind  of  tongue  that  unites 
them  is  finally  broken,  and  the  cure,  when  it  is  effected, 
is  made  by  the  obliteration  of  the  vessel. 

3d.  In  complete  transverse  sections,  death  does  not 
take  place  unless  there  is  at  the  same  time  denudation  of 
the  artery.  When  the  sheath  is  left,  the  wound  is  almost 
always  cured  in  animals  by  an  obliteration  of  the  artery. 
The  two  ends  retract  into  the  interior  of  their  cellular 
canal,  which  thus  extends  beyond  their  extremit)'.  The 
hemorrhage  brings  on  weakness  and  syncope ; the  blood 
is  effused  and  finally  forms  a coagulum  which,  filling  the 
sheath,  surrounds  the  artery  and  shuts  its  extremity. 
When  the  force  of  the  heart  returns,  the  coagulum  resists 
and  the  hemorrhage  does  not  again  come  on.  The  blood 
coagulates  in  the  artery  as  far  as  the  first  collateral 
branches,  the  parietes  of  the  vessel  contract,  a cicatrix  is 
formed  at  each  end  and  obliteration  takes  place.  This 
obliteration  is,  according  to  Jones,  the  result  of  a lym- 
phatic effusion  which  is  poured  out  in  the  artery  near  its 
extremity,  between  the  external  and  internal  coagula. 
When  this  takes  place,  the  coagula  are  absorbed  and  dis- 
appear. 


96 


ADDITIONS  TO  THE 


The  same  things  do  not  always  take  place  in  man.  In 
punctures,  for  example,  it  is  extremely  rare  that  the  cure 
is  solid,  unless  the  arterj"  is  at  the  same  time  obliterated. 
The  hemorrhage  in  this  case  left  to  itself,  continues  with- 
out interruption  ; the  blood,  if  it  does  not  flow  out,  is 
effused  into  tbe  cellular  texture,  and  produces  a diffused 
or  primary  false  aneurism.  Suppose  that  by  compres- 
sion or  rest,  a coagulum  should  be  formed,  and  a cicatrix 
even  established,  the  cure  may  be  only  apparent.  Though 
this  state  may  continue  for  )^ears,  the  blood  will  finally 
remove  or  break  these  feeble  barriers  and  a tumour  will 
appear ; this  will  be  a circumscribed  or  consecutive 
false  aneurism.  Such  is  at  least  the  result  of  facts  ob- 
served up  to  the  present  time.  It  is  true  that  we  are 
almost  always  ignorant  of  the  direction  and  extent  of  the 
wound  ; and,  as  has  been  seen,  the  termination  is  very 
different  in  this  respect.  It  is  thus  extremely  probable 
that  a puncture  made  lengthwise  would  heal  as  well  in 
man  as  it  does  in  animals. 

Spontaneons  cure  is  likewise  very  rare,  in  man,  of 
wounds  which  comprehend  the  whole  circumference  of 
the  artery  ; and,  unless  the  caliber  be  very  small,  these 
wounds,  left  to  themselves,  are  uniformly  fatal.  It  is 
necessary  however  to  except  from  them,  1st,  certain  cases 
in  which,  notwithstanding  the  considerable  size  of  the 
vessels  opened,  a coagulum  formed  during  a syncope 
has  been  sufficiently  powerful,  or  rather  the  circulation  has 
been  sufficiently  feeble,  so  that  the  hemorrhage  has  not 
reappeared  and  the  adhesive  inflammation  has  had  time  to 
take  place  ; examples  of  this  kind  are  cited  by  Boerhaave, 
Garengeot  and  others.  2d.  Wounds  from  fire-arms  and 
those  which  result  from  the  action  of  fire  and  caustics 
here  it  is  the  eschars  which  prevent  the  hemorrhage,  and 
when  they  fall  off'  the  vessels  are  often  obliterated.  3d. 


VASCULAR  SYSTEM  WITH  RED  BLOOD 


97 


Lacerated  wounds  ; I have  collected  a number  of  observa- 
tions respecting  them  made  by  authors  ; the  most  re- 
markable is  the  case  of  Samuel  Wood,  related  in  the 
Philosophical  Transactions,  and  since  in  various  works. 
In  some  of  these  observations,  death  has  been  the  con- 
sequence of  a copious  hemorrhage  ; but  in  the  greatest 
number,  as  also  in  the  experiments  which  I have  made 
upon  animals,  a cure  has  taken  place.  Besides  the  retrac- 
tion and  contraction  noticed  by  Bichat,  two  additional 
causes  are  opposed  in  this  case  to  the  flow  of  blood,  and 
favour  the  obliteration  of  the  artery.  In  fact,  at  the  instant 
even  of  the  accident,  this  yields  and  is  elongated  before 
breaking  ; but  the  internal  rnembranes,  less  extensible, 
are  torn  at  first  unequally  and  in  different  places,  and 
then  are  completely  separated,  whilst  the  cellular  coat 
continues  to  stretch,  approximating  more  and  more  the 
axis  of  the  vessel,  like  a tube  of  melted  glass  drawn  at 
both  ends.  When  the  separation  is  completed,  the  artery 
exhibits  then  at  its  extremity  a conical  elongation,  ter- 
minated by  a narrow  opening,  and  in  its  interior  irregu- 
lar shreds  which  obstruct  its  cavity.  This  last  circum- 
stance appears  to  be  the  most  important  of  the  three,  for, 
1st,  the  retraction  is  often  wanting,  the  end  of  the  artery 
is  pendent,  and  yet  there  is  no  hemorrhage  ; 2d,  by  cut- 
ting in  an  animal  the  summit  of  the  kind  of  cone  which 
the  artery  forms,  the  flow  of  blood  does  not  return, 
unless  the  section  be  made  above  the  internal  lacerations. 

Solutions  of  continuity,  which  affect  but  one  part  of 
the  arterial  membrane,  act  upon  the  internal  or  external 
coats.  Hunter  and  Home  have  seen,  that  if  the  internal 
membrane  be  laid  bare  in  dogs,  by  cutting  the  external 
and  middle  ones,  there  results  from  it  an  albuminous 
exudation,  by  which  the  thickness  of  the  artery  is  in- 
creased. They  have  even  removed  these  membranes  to 
13 


98 


ADDITIONS  TO  THE 


a certain  extent,  without  the  internal  one  being  distended 
by  the  blood.  This  must  however  take  place  in  man 
^n  what  is  called  mixed  or  internal  mixed  aneurism, 
aneurysma  herniam  arterise  sistens,  in  which  it  is 
supposed  the  sac  is  formed  by  the  internal  membrane 
dilated.  Many  authors  reject  this  kind  of  aneurism, 
but  examples  of  it  have  been  given. 

It  has  been  thought,  that  the  distension  of  the  arteries 
during  life,  in  violent  motions,  might  produce  the  rupture 
of  the  internal  membranes  and  thus  dispose  to  aneurism. 
But  the  arteries  are  everywhere  so  arranged  that  it  is 
impossible  that  their  distension  can  occasion  even  a par- 
tial rupture,  of  which  it  is  easy  to  be  convinced  on  the 
dead  body  ; this  would  not  happen  unless  their  parietes 
were  the  seat  of  some  organic  disease.  This  internal 
rupture  is  observed,  on  the  contrary,  under  the  following 
circumstances.  1st.  By  pressing  with  a pincers  an  artery 
of  an  animal,  we  effect  the  division  of  the  internal  and 
middle  membranes,  the  external  one  remaining  whole  ; 
the  small  wound,  which  results  from  it,  cicatrizes,  and 
the  artery  loses  nothing  of  its  strength  in  this  place  ; its 
parietes  are  even  rather  thicker ; when  there  is  a great 
number  of  lacerations,  the  obliteration  of  the  artery  is 
sometimes  the  consequence.  2d.  What  in  the  preceding 
case,  happens  to  a moderate  extent,  takes  place  circularly 
from  a ligature,  as  has  been  elsewhere  said.  There  is 
also  this  difference,  that  the  edges  of  the  wound  being  in 
contact  are  agglutinated  by  a mechanism  analogous  to 
that  of  the  reunion  of  wounds  by  the  first  intention.  The 
artery  is  then  obliterated  ; the  blood  is  coagulated  above 
and  below  the  cicatrix,  as  far  as  the  first  collateral 
branches  ; the  obliteration  goes  all  this  extent.  If  these 
branches  are  very  near,  the  coagulum  being  very  weak, 
the  cicatrix  is  not  maintained,  and  a hemorrhage  may  take 


VASCULAR  SYSTEM  WITH  RED  BLOOD. 


99 


place  when  the  ligature  comes  off,  and  even  before,  when 
the  membranes  begin  to  be  broken.  Jones  says  that  it 
is  not  necessary  for  a ligature  to  remain  applied  upon  an 
artery  in  order  that  obliteration  should  take  place  ; by 
placing  many  ligatures  and  removing  them  successively, 
he  has  seen  this  effect  produced.  Travers  assures  us  that 
obliteration  is  certain  when  the  ligature  has  remained 
applied  for  an  hour ; though  the  blood  often  resumes  its 
course  at  the  end  of  that  time,  the  artery  is  not  the  less 
obliterated,  according  to  the  experiments  of  this  author. 
I have  uniformly  seen  in  my  experiments  the  artery  re- 
main permeable,  when  the  ligature  has  been  removed 
even  at  the  end  of  twenty-four  hours  ; it  was  not  closed 
definitively  until  the  adhesion  was  established  at  the  mo- 
ment the  ligature  came  off,  which  commonly  happened 
at  the  end  of  eight  and  forty  hours.  3d.  If  an  aneurism 
be  of  any  standing,  the  internal  membranes  yield  to  the 
distension,  as  w'e  have  seen  ; they  are  torn  by  the  mere 
effort  of  the  blood  or  by  any  external  violence.  The 
tumour,  which  is  then  formed  by  the  cellular  coat  alone, 
makes  m.ore  rapid  progress  ; the  blood  coagulates  in  its 
interior  and  forms  fibrous  layers,  the  density  of  which 
increases  as  they  are  removed  from  the  axis  of  the  vessel ; 
the  sac,  freed  from  these  coagula,  exhibits  on  its  internal 
surface  an  irregular  line  which  indicates  the  point  where 
the  membranes  cease  ; these  are  sometimes  floating,  and 
exhibit  a sort  of  incomplete  partition  which  separates  the 
cavity  of  the  sac  from  that  of  the  artery  ; this  is  the 
true  aneurism,  arrived  to  that  degree  which  some  have 
called  external  mixed.  In  time,  the  cellular  coat  itself 
is  affected,  it  is  destroyed,  and  the  sac  is  formed  only  of 
the  cellular  texture  and  the  other  surrounding  pai’ts.  4th. 
In  another  species  of  aneurism,  which,  at  an  advanced 
period,  does  not  differ  sensibly  from  the  preceding,  and 


100 


ADDITIONS  TO  THE 


which  has  been  designated  under  the  same  name,  but 
■which  others  call  spontaneous  aneurism,  the  destruction 
of  the  rnembranes  precedes  the  formation  of  the  tumour. 
This  destruction  is  here  owing  to  the  ulceration  or  rup- 
ture which  the  internal  membrane  experiences  in  organic 
diseases  ; the  blood  is  then  confined  below  this  membrane 
and  distends  the  cellular  coat.  This  variety  of  aneurism 
is  perhaps  the  most  common  ; but  it  is  not  correct  to  say 
that  all  begin  in  this  way.  Moreover,  the  ulceration  of 
the  internal  membrane  is  not  always  followed  by  aneu- 
rism ; M,  Cruveilhier  has  found  this  membrane  des- 
troyed as  well  as  the  fibrous,  and  yet  there  was  no  dila- 
tation of  the  cellular  coat. 

Foreign  bodies,  in  contact  with  the  arterial  texture, 
inflame  and  often  ulcerate  it  so  as  to  open  the  cavity  of 
the  vessel.  If  these  bodies  act  by  approximating  to  each 
other  the  parietes  of  the  artery,  they  produce  an  adhesion 
of  these  parietes.  When  they  make  a circular  constric- 
tion, like  a ligature,  they  produce  mortification  in  the 
narrow  portion  which  they  embrace,  and  are  afterwards 
removed  with  it ; this  is  what  takes  place  with  a ligature 
at  the  end  of  from  eight  to  twenty  days. 

We  know  the  frequency  of  arterial  ossifications  ; they 
exhibit  many  forms.  There  are  circular  ones  which 
invade  arteries  almost  in  their  whole  length  ; they  ex- 
tend to  the  peculiar  membrane,  and  are  sometimes  attend- 
ed with  a contraction  and  obstruction  of  the  vessel  ; that 
species  of  gangrene  which  is  called  senile  is  oftentimes 
the  consequence  of  it.  In  other  cases,  the  incrustation 
is  much  more  limited  ; there  is  only  on  the  interior  of 
the  artery  a great  number  of  small  white  marks,  super- 
ficial and  but  slightly  prominent.  Between  these  two 
extremes  are  found  yellowish  plates,  semi-transparent  and 
irregular,  which  appear  at  first  to  be  situated  in  the  space 


VASCULAR  SYSTEM  WITH  RED  BLOOD. 


101 


between  the  two  membranes,  but  which  the  blood  after- 
wards touches  immediately,  because  the  inteimal  one  is 
destroyed  on  their  surface. 

The  cartilaginous  transformation  has  also  been  observed 
in  the  arterial  texture.  It  has  its  seat  in  the  internal 
membrane,  and  is  characterized  by  plates  of  a white 
colour,  prominent,  fibrous  and  very  dense.  The  carti- 
laginous state  almost  uniformly  precedes  the  ossifica- 
tions of  the  arteries  which  take  place  in  adult  age,  whilst 
those  of  old  people  are  owing  simply  to  irregular  deposi- 
tions of  calcareous  matter. 

The  arteries  are  changed  into  a fibrous  or  ligamentary 
texture,  whenever  their  cavity  is  obliterated  naturally  or 
preternaturally.  This  texture  in  time  becomes  more 
delicate,  and  disappears  itself  or  is  confounded  with  the 
cellular  texture. 

There  are  some  morbid  alterations  peculiar  to  the  arte- 
rial texture ; they  have  hardly  any  thing  in  common 
with  those  which  afiect  the  other  textures.  1st.  Some- 
times in  aneurisms  the  internal  membrane  is  found  thick- 
ened, softened,  and  as  it  were  fungous.  2d.  Growths 
similar  in  form  to  those  which  are  the  product  of  syphilis 
have  been  met  with  in  the  aortic  valves ; Hodgson  has 
even  seen  them  in  the  femoral  artery.  3d.  The  deposi- 
tion of  a pultaceous  substance  on  or  under  the  internal 
membrane  is  a much  more  frequent  alteration.  It  has 
been  compared  to  steatoma;  but  there  is  a greater  anal- 
ogy between  it  and  the  tubercular  affection.  Sometimes 
this  substance,  irregularly  disseminated,  forms  on  the  inte- 
rior of  the  artery  small  yellowish  granulations,  covered 
with  an  extremely  delicate  pellicle ; sometimes,  accumu- 
lated between  the  internal  and  the  fibrous  coat,  it  forms 
round  masses,  which  obstruct  more  or  less  tbe  cavity  of 
the  vessel,  or  even  real  centres,  filled  with  a purulent. 


102 


ADDITIONS  TO  THE 


opake  and  3-cIlo\vish  fluid.  The  tumour,  in  the  last  case, 
terminates  sometimes  by  opening  into  the  artery.  At 
others,  the  substance  hardens  and  assumes  all  the  charac- 
ters of  the  osseous  productions  ; it  then  contains  much 
phosphate  of  lime.  This  affection  is  often  connected 
with  the  osseous  transformation.  Both  are  common  in 
aneurisms  especially  the  first. 

The  arteries  partake  of  the  affections  of  the  organs  of 
which  they  make  a part.  Their  destruction,  in  cancer- 
ous, tubercular  and  other  affections,  produces  various 
hemorrhages ; sometimes,  however,  their  obliteration 
prevents  the  flow  of  blood. 

III.  Alterations  in  the  Development. 

Without  speaking  of  the  numberless  varieties  of  origin, 
distribution,  &c.  observed  in  the  arteries,  and  which, 
being  all  different  from  the  natural  arrangement,  exert 
however  only  a very  limiled  influence  upon  the  cir- 
culation, it  will  be  sufficient  to  point  out  some  of  those 
the  importance  of  which  is  greater  in  this  respect.  The 
heart  has  been  seen  wanting  with  all  the  superior  parts, 
and  consequently  also  their  vessels.  In  the  heart  itself, 
it  sometimes  happens  that  there  is  but  one  auricle  and  one 
ventricle  ; the  pulmonary  artery  arises  then  from  the 
aorta.  Or  it  is  the  partition  between  the  ventricles  that 
is  perforated ; or  it  is  the  foraman  ovale  which  is  pre- 
served, or  the  ductus  arteriosus  that  remains  permeable. 
In  one  instance  the  aorta  terminated  immediately  after 
its  ascending  portion,  and  the  pulmonary  artery  continued 
it  below.  In  another,  the  trunk  of  the  first  was  bifur- 
cated so  as  to  embrace  the  trachea  and  oesophagus. 

Besides  the  capillaries  which  are  developed  under 
many  circumstances,  arteries  of  a certain  size  are  some- 


VASCULAR  SYSTEM  WITH  RED  BLOOD. 


103 


times  preternaturally  produced.  Charles  Parry  says  that 
he  has  found,  in  a sheep  in  whom  he  had  divided  the 
carotid  artery,  new  arteries  which  went  parallel  from 
one  of  the  two  ends  to  the  other,  the  whole  extent  of 
the  cicatrix,  and  thus  reestablished  the  circulation. 


ADDITIONS 


TO  THE 


VASCULAR  SYSTEM  WITH  BLACK  BLOOD. 


Venous  Valves. 

Page  406, — “ We  find  in  the  works  of  Haller  very- 
minute  descriptions  of  the  general  arrangement,  form 
and  position  of  the  vascular  folds  of  which  we  are  treat- 
ing.” 

The  following  should  be  added  to  what  Bichat  has 
said, 

1st.  These  valves  are  more  numerous  in  the  superficial 
than  in  the  deep-seated  veins,  in  those  of  the  extremities, 
than  in  those  in  the  interior  of  the  trunk ; the  superior 
extremities  have  fewer  of  them  than  the  inferior.  In  gen- 
eral they  are  not  found  in  the  branches  of  communication 
14 


106 


ADDITIONS  TO  THE 


of  the  veins,  such  as  the  median  of  the  arm.  The  veins 
of  the  heart  are  entirely  destitute  of  them  ; it  is  usually  the 
same  with  those  of  the  uterus.  The  spermatic  veins  of 
woman  have  no  valves,  those  of  man  have.  It  is  on  the 
inferior  part  of  the  extremities  that  there  are  the  most  of 
them  ; the  veins  of  the  exterior  of  the  head  contain  but  a 
small  number ; there  are  usually  some  at  the  opening  of 
the  branches  in  the  trunks. 

2d.  The  loose  edge  of  these  valves  is  thicker  than  the 
rest,  and  forms,  like  the  adherent  one,  a sort  of  cushion. 

3d.  Above  the  valves,  the  vein  exhibits  a dilatation 
which  produces  a depression  on  the  interior  and  a pro- 
jection on  the  exterior  of  the  vessel.  This  arrangement, 
in  some  cases,  gives  rise  to  knots,  which  are  only  seen 
at  the  places  where  the  valves  are. 

4th.  Besides  the  two  membranous  layers  which,  it  is 
said,  form  the  valves,  though  they  can  in  no  way  be  sepa- 
rated, fibres  appear  to  enter  into  the  composition  of  these 
folds  ; at  least,  by  examining  them  upon  one  of  their 
faces,  white,  interlaced  filaments  can  often  be  distinguished. 
Sometimes  also  the  valves  are  perforated  and  formed  by 
an  areolar  texture. 

5th.  Perrault  has  established  many  species  of  valves 
according  to  the  form  which  they  affect.  The  only  real 
difference  in  this  respect  is,  that  in  the  great  veins  they 
are  very  broad,  and  the  curve  which  they  describe  small, 
whilst  in  the  small  ones  their  want  of  breadth  renders 
this  curve  more  evident.  The  valves  are  also  broader  at 
the  angles  of  union  of  the  branches  with  the  trunks. 
This  is  independent  of  the  state  of  contraction  or  dilata- 
tion of  the  veins,  which  has  an  influence  upon  the  size  of 
the  valves,  as  has  been  seen  above. 


VASCULAR  SYSTEM  WITH  BLACK  BLOOD. 


107 


Contractility  of  the  Veins. 

Page  415. — The  question,”  (viz.  whether  the  veins 
are  'irritable,)  “ is  not,  then,  fully  settled,  though  I in- 
cline much  more  to  the  belief  that  there  is  no  venous  irri- 
tability.” 

Whatever  may  be  the  name  under  which  we  would 
wish  to  designate  the  contractile  force  of  the  venous  tex- 
ture, we  cannot  refuse  to  admit  that  this  texture  pos- 
sesses, during  life,  a property  very  different  from  all  those 
which  are  found  in  it  after  death,  and  consequently  one 
essentially  vital.  It  is  in  virtue  of  this  jjroperty  that  a 
vein  opened  between  two  ligatures  drives  out  from  a dis- 
tance the  blood  which  it  contains,  whilst  in  the  same  ex- 
periment made  upon  the  dead  body,  the  blood  only  oozes, 
the  effect  alone  of  the  elastic  spring  of  the  parietes.  The 
contractility  of  texture,  in  the  sense  which  Bichat  gives 
to  this  word,  cannot  be  the  cause  of  this  phenomenon, 
since  it  exists  after  death  as  well  as  during  life.  If  we 
compress  in  a living  animal  the  principal  artery  of  a limb, 
taking  care  to  keep  the  limb  in  a horizontal  position, 
we  shall  see  the  sub-cutaneous  veins  gradually  contract, 
though  the  circulation  may  be  suspended  in  the  artery,  and 
empty  themselves  of  all  the  blood  which  they  contained 
at  the  moment  of  the  experiment.  In  the  dead  body,  the 
veins  do  not  contract  thus  upon  the  blood  they  contain  ; 
their  size  depends  alwaj^s  upon  the  quantity  of  this  fluid 
which  remains  in  them  at  the  instant  of  death.  More- 
over, it  is  with  this  contraction  as  with  that  of  the  arterial 
texture,  it  cannot  be  referred  to  any  of  the  forces  which 
preside  over  the  other  kinds  of  contraction.  The  galvanic 


lOS 


ADDITIONS  TO  THE 


stimulus  appears  to  be  capable  of  producing  it,  though 
this  has  been  denied. 

Verschuir  calls  this  contractile  faculty  of  the  venous 
texture  irritability  ; Whytt  gives  it  the  name  of  vibra- 
tory motion  of  the  veins  ; Kramp  designates  it  simply 
under  that  of  vital  force  of  the  veins,  and  others  refer  it 
to  tone.  I shall  not  decide  which  of  these  denominations 
is  preferable  ; I would  merely  observe,  that  there  is  in  the 
venous  motions  during  life  something  besides  the  effect 
of  the  elasticity  of  inanimate  matter. 

Venous  Circulation.  '' 

Page  420. — “ The  blood  is  evidently  beyond  the  influ- 
ence of  the  heart  when  it  arrives  in  the  veins.” 

This  opinion  is  diametrically  opposed  to  that  of  Harvey 
and  the  mechanicians  of  his  time,  which  some  modern 
physiologists  have  adopted.  They  consider  the  heart  as 
the  sole  agent  of  circulation,  venous  as  well  as  arterial  ; 
Harvey  compared  it  to  a suction  and  forcing  pump,  which 
on  the  one  hand  attracts  the  venous  blood,  and  on  the 
other  sends  out  the  arterial.  There  is  no  doubt  exag- 
geration in  this  manner  of  considering  it,  though  it  would 
be  wrong  wholly  to  reject  the  influence  of  the  heart 
upon  the  motion  of  the  blood  in  the  veins.  The  capil- 
lary and  venous  action  are  the  principal  causes  of  this 
motion ; but  the  contraction  of  the  ventricles  should 
be  enumerated  among  the  secondary  causes.  One  fact 
will  be  sufficient  to  prove  this.  Open  a vein  and  observe 
the  jet  of  blood  which  flows  from  it ; at  the  end  of  some 
time,  this  jet  will  be  no  longer  uniform,  it  will  be  evi- 
dently raised,  and  the  blood  will  come  out  quicker  at 


VASCULAR  SYSTEM  WITH  BLACK  BLOOD. 


109 


each  contraction  of  the  ventricles.  This  influence  is  then 
real,  though  much  less  evident  than  in  the  arteries. 

Development  of  the  Venous  System. 

Page  425. — “ The  veins  have  in  the  foetus  an  arrange- 
ment inverse  of  that  of  the  arteries ; they  are  in  propor- 
tion much  less  developed.” 

By  applying  to  man  the  labours  of  Haller,  Pander  and 
others,  upon  the  development  of  the  blood  vessels  of  the 
chick,  it  would  follow  from  it  that  a part  of  the  venous 
system  is  earlier  developed  than  the  arterial  system.  The 
first  vessels  that  are  discovered  are  the  small  branches  of 
the  vein  of  the  yolk,  or  the  umbilico-mesenteric.  This 
vein  itself,  as  well  as  the  vena  porta,  is  distinct  when  the 
aorta  hardly  exists.  J.  F.  Meckel  thinks  nevertheless 
that,  from  the  arrangement  of  the  sanguineous  system  in 
some  monstrous  foetuses,  and  the  manner  in  which  this 
system  is  complicated  in  the  scale  of  beings,  it  would  be 
possible  that  the  aorta  should  be  formed  in  man  at  the 
same  time  as  the  first  veins,  or  even  before  them.  If  so, 
this  artery  must  exist  before  the  heart,  and  communicate 
directly  with  the  vena  porta  before  the  formation  of  this 
viscus.  With  this  exception  only  in  regard  to  the  um- 
bilico-mesenteric vessels,  the  veins  in  general  are  not 
developed  till  after  the  corresponding  arteries.  As  it 
regards  the  development  of  the  pulmonary  artery,  what 
I have  said  in  the  vascular  system  with  red  blood  may 
be  seen. 


110 


ADDITIONS  TO  THE 


MORBID  ANATOMY  OF  THE  VASCULAR  SYSTEM  WITH 
BLACK  BLOOD. 

I.  Mteration  in  the  external  forms. 

The  veins,  like  the  arteries,  experience  total  or  partial 
dilatations  ; this  is  what  constitutes  varices.  The  fre- 
quency of  this  affection  in  the  inferior  extremities  is  well 
known  ; the  reason  of  it  has  been  given  above.  It  is  also 
quite  often  met  with  in  the  veins  of  the  rectum,  the  blad- 
der and  genital  organs,  and  in  the  sub-cutaneous  veins 
of  the  anterior  parietes  of  the  abdomen.  The  deep-seated 
veins  are  not  exempt  from  it,  though  they  are  much  more 
rarely  affected  than  the  superficial  ones.  Morgagni  has 
found  the  azygos  vein  considerably  dilated  ; the  jugulars 
and  the  crural  sometimes  become  varicose.  In  some 
cases,  the  whole  venous  system  exhibits  :a  very  evident 
increase.  Puschett,  who  has  recently  published  in  Ger- 
many a very  extensive  treatise  on  the  diseases  of  the 
veins,  has  insisted  very  much  on  this  general  dilatation, 
which,  in  his  opinion,  performs  an  important  part  in  a 
great  number  of  diseases.  The  dilatation  may,  not  as  we 
have  seen,  be  confined  to  a single  vein,  but  extend  to  all 
its  divisions.  The  increase  of  size  takes  place  then  not 
only  in  the  transverse  direction  ; the  veins  form  curves 
which  are  evidently  owing  to  their  increase  in  length. 
Finally  there  are  dilatations  still  more  limited  which 
affect  but  a part  of  the  circumference  of  the  vessel.  , 

The  state  opposite  to  the  preceding,  or  the  diminution 
of  capacity  of  the  venous  system,  is  by  no  means  so 
common.  Yet  it  is  seen  under  some  circumstances,  either 
in  the  whole  system,  or  only  in  some  veins  in  particular. 


VASCULAR,  SYSTEM  WITH  BLACK  BLOOD. 


Ill 


This  diminution  can  extend  even  to  obliteration.  There 
are  examples  of  the  spontaneous  obliteration  of  the  venous 
trunks  themselves,  as  of  the  vense  cavae,  jugulars,  &c. 

II.  Alterations  in  the  Organization. 

The  inflammation  of  the  veins  takes  place  under  many 
circumstances.  1st.  It  has  been  seen  to  extend  a greater 
or  less  distance  after  the  operation  of  blood-letting.  It  is 
always  on  the  side  of  the  heart  that  it  is  propagated  in 
this  case,  and  never  on  that  of  the  capillary  vessels.* 
Death  even  may  be  the  consequence  of  it.  2d.  Tying 
the  veins,  which  has  been  sometimes  done  in  amputations 
has  been  followed  by  inflammation,  which,  as  in  the  pre- 
ceding case,  extends  towards  the  heart  for  a greater  or  less 
distance.  3d.  Tying  the  umbilical  cord  appears  to  have 
produced  the  same  effect.  Meckel  the  elder,  and  Osian- 
der  have  related  examples  of  it.  4th.  Veins  affected  with 
varices  and  tied  above  the  disease  have  also  exhibited  this 
phenomenon.  5th.  In  very  extensive  phlegmonous  in- 
flammations, in  those,  for  example,  which  come  after  par- 
turition, in  the  abscesses  and  gangrene  which  succeed 
them,  the  veins  are  often  found  more  or  less  inflamed  on 
the  exterior  as  well  as  the  interior.  This  inflammation 
sometimes  extends  far  beyond  the  diseased  part. 

There  is  no  vein  which  does  not  sometimes  exhibit 
traces  of  inflammation,  from  some  of  the  causes  that  we 
have  just  pointed  out.  The  disorders  produced  by  this 
affection  are,  a redness  more  or  less  considerable  on  the 
internal  membrane,  with  a thickening  of  the  two  other 
coats ; purulent  collections  of  different  kinds  around  the 

* This  rule  however  is  not  without  exceptions.  Abernethy  has  seen 
the  vein  inflame  below,  almost  to  the  Wrist,  after  bleedina:  in  the  arm, 
and  remain  sound  above,  that  is  to  say,  on  the  side  of  the  heart. 


112 


ADDITIONS  TO  THE 


vessel  or  even  in  its  internal  cavity,  fibrous  concretions 
which  obstruct  this  cavity  more  or  less,  sometimes  even 
the  complete  obliteration  of  the  vein,  in  some  cases  a 
remarkable  hardness,  and  at  other  times  ulcerations  ; such 
are  the  principal  disorders  to  which  this  afiection  gives 
rise. 

It  becomes  salutary,  on  the  contrary,  when,  as  after 
venesection,  it  is  limited  to  the  lips  of  the  wound,  and 
does  not  extend  beyond  the  degree  necessary  for  its  ad- 
hesion. Every  one  knows  that  these  punctures  heal  with 
the  greatest  ease ; it  is  also  known  that  at  the  end  of 
twenty-four  hours  the  means  of  union  is  still  not  very 
firm,  that  it  can  even  be  broken  by  a moderate  effort,  and 
that  it  is  not  till  afterwards  that  there  is  a real  cicatrix. 
The  mechanism  of  the  union  is  here  the  same  as  in 
wounds  of  the  other  textures,  whilst  as  it  regards  the 
arteries,  this  union  has  hitherto  been  only  observed  upon 
animals.  If  we  may  credit  Mr.  Travers,  the  internal 
membrane  of  the  veins  does  not  partake  of  their  adhe- 
sive inflammation. 

The  same  author  believes,  that  in  the  obliteration  of 
the  veins  which  follows  their  transverse  division,  it  is  not 
the  adhesion  of  the  internal  membrane,  but  the  thicken- 
ing of  the  parietes,  which  closes  the  cavity  of  the  vessel. 
His  observations  upon  this  subject  should  be  repeated. 

Wounds  produced  by  an  external  cause  resemble  spon- 
taneous ruptures.  Morgagni  cites  a case  of  this  kind,  in 
which  the  azygos  vein  exhibited  an  oval  opening  in  a 
woman  who  died  of  phthisis.  The  blood  was  effused  in 
the  thorax  ; the  vein,  though  partly  flattened,  had  still 
the  size  of  the  vena  cava.  Convulsive  motions  have  ap- 
peared sometimes  to  be  the  cause  of  these  ruptures. 

Wounds  made  in  the  parietes  of  the  veins  may  affect 
at  the  same  time  an  artery  which  is  united  to  them  ; if, 


VASCULAR  SYSTEM  WITH  BLACK  BLOOD, 


113 


ifl  this  case,  the  external  wound  cicatrizes,  the  opening  of 
communication  subsisting  between  the  artery  and  the 
vein,  there  will  result  from  it  the  disease  described  under 
the  name  of  aneurismal  varix,  in  which  the  blood,  pass- 
ing from  the  artery  to  the  vein  at  each  contraction  of  the 
ventricle,  distends  this  last  and  produces  in  it  a pulsatory 
motion  analogous  to  that  of  the  arteries.  Sometimes 
there  is  merely  a round  opening,  formed  of  the  corres- 
ponding parietes  of  the  two  vessels  ; sometimes  there  is  a 
consecutive  false  aneurism,  which  is  found  between  the 
artery  and  the  vein.  It  is  in  this  last  case  that  the  dis- 
ease deserves  the  name  of  varicose  aneurism.  The  bend 
of  the  elbow  is  the  most  frequent  seat  of  this  affection,  of 
which' various  examples  are  found  in  authors,  particularly 
in  the  work  of  Hodgson  on  the  Diseases  of  the  Arteries. 

Bichat  has  already  remarked  how  rare  osseous  trans- 
formations are  in  the  vascular  system  with  black  blood  ; 
it  is  even  one  of  the  characters  which  he  has  given  to  the 
common  membrane  which  lines  the  whole  interior  of  this 
system.  Yet  this  membrane  is  not  entirely  exempt  from 
them.  Morgagni  found  in  a young  girl  the  sigmoid 
valves  of  the  pulmonary  artery  partly  cartilaginous  and 
already  exhibiting  the  commencement  of  ossification. 
M.  Corvisart  has  many  times  met  with  this  alteration  in 
these  valves,  as  well  as  in  the  tricuspid.  The  veins  them- 
selves are  susceptible  of  ossification  in  old  people,  espe- 
cially on  the  side  where  they  touch  an  artery.  There  is 
sometimes  found  in  the  veins  small,  hard,  round  bodies, 
which  might  be  taken  at  first  sight  for  osseous  produc- 
tions. Some  have  even  supposed  that  they  are  formed  at 
first  in  the  parietes  of  the  veins ; others  have  said  that  it 
was  in  the  substance  of  the  valves  ; Hodgson  thinks  that 
their  primitive  seat  is  on  the  exterior  of  the  vein.  These 
bodies,  which  I have  many  times  had  occasion  to  examine, 
15 


114 


ADDITIONS,  &c. 


have  appeared  to  me  to  be  real  concretions,  phlebolithes. 
They  are  usually  found  in  lateral  dilatations  in  which 
the  blood  is  stagnant  ; there  is  observed  in  their  structure 
nothing  which  resembles  the  osseous  texture  ; they  seem 
to  be  formed  on  tlie  contrary  oi  layers  superadded  to  each 
other,  and  have  around  them  a very  evident  coagulum. 
They  are  found  also  of  different  degrees  of  consistence. 
The  veins  which  exhibit  this  alteration  the  most  frequently 
are  those  in  which  the  course  of  the  blood  is  the  most  ex- 
posed to  being  retarded  ; thus  it  is  very  common  in  veins 
which  occupy  the  interior  of  the  pelvis,  the  neighbour- 
hood of  the  arms,  &c. 

The  venous  texture  has  not  any  morbid  afiection  which 
is  peculiar  to  it ; it  partakes  of  those  of  the  other  organs. 

III.  Mterations  in  the  development. 

Are  varieties  in  the  situation,  origin  and  distribution  of 
the  veins  more  frequent  than  those  of  the  arteries,  as 
Haller  thought  ? Meckel  maintains  the  contrary,  and  that 
the  veins  seem  to  have  more  varieties,  only  because  their 
number  is  greater.  There  is  perhaps  exaggeration  on 
both  sides  ; yet  it  is  evident  that  in  the  great  trunks 
the  arrangement  is  much  more  constant  in  the  veins  than 
in  the  arteries. 

There  are  veins  in  all  parts  as  there  are  arteries.  The 
following  is  a proof  of  it ; a false  membrane,  which  was 
found  in  the  tunica  arachnoides,  and  adhered  to  the 
serous  membrane  only  by  one  of  its  edges,  at  the  superior 
longitudinal  sinus,  and  was  entirely  free  elsewhere,  was 
injected  with  mercury,  which  enabled  me  to  see  veins 
going  to  this  sinus.  i 


ADDITIONS 


TO  THE 

CAPILLARY  SYSTEAIS. 


Continuation  of  the  Arteries  with  the  Veins,  the 
Exhalants,  fyc. 

Page  19,  vol.  2d. — ‘‘  It  has  been  asked,  if  there  was 
any  thing  intermediate  between  the  arteries  and  the 
veins,  inspection  proves  that  the  capillary  system  alone 
is  there.” 

It  was  formerly  thought,  in  fact  even  since  the  beautiful 
discovery  of  Harvey  of  the  circulation  of  the  blood,  that 
there  was  a texture  intermediate  between  the  last  extremi- 
ties of  the  arteries  and  the  first  branches  of  the  veins. 
This  opinion  was  founded  on  the  fact  that  oftentimes  in 
injections,  the  substance  pushed  into  the  arteries,  instead  of 
returning  directly  by  the  veins,  seems  at  first  to  be  infil- 
trated in  the  surrounding  cellular  texture.  It  was  after, 
wards  perceived,  that  this  infiltration  was  accidental,  that 


IIG 


ADDITIONS  TO  THE 


certain  substances  only,  a solution  of  glue  for  example, 
were  capable  of  infiltrating,  whilst  others  do  not  exhibit 
this  phenomenon.  The  existence  of  an  intermediate  tex- 
ture was  then  rejected,  especially  as  no  one  had  seen  this 
texture.  Finally,  Malpighi  appears  to  have  been  the  first 
who  proved  by  microscopical  examination,  the  direct  con- 
tinuation of  the  arteries  with  the  veins,  so  well  demon- 
strated since  by  the  experiments  of  Spallanzani  and  espe- 
cially of  Leuwenhock.  At  the  present  day  any  one  may 
see  this  continuation  who  will  take  the  trouble  ; for  this 
purpose,  the  transparent  parts  of  animals  are  chosen,  as 
the  mesentery  of  frogs,  the  tail  and  limbs  of  tadpoles,  that 
of  fishes,  &c.  Injections  driven  through  the  arteries  not 
only  return  by  the  veins,  but  the  reverse  also  takes  place, 
if  the  valves  do  not  prevent  it. 

The  continuation  of  the  arteries  in  the  exhalant  vessels 
cannot  exist  unless  these  vessels  really  exist ; now,  we 
shall  see  hereafter  that  this  point  is  still  very  obscure. 
The  communication  with  the  excretories  is  not  demon- 
strated as  it  regards  all  the  glands  ; there  are  some  in 
which  injections  have  not  passed  from  the  arteries  into 
those  tubes ; the  microscope  has  not  yet  shown  us  the 
continuation  of  these  two  orders  of  vessels  ; we  know  not, 
if  in  the  glands  even  in  which  they  evidently  communi- 
cate, there  be  not  an  intermediate  substance. 

The  last  extremities  of  the  arteries  communicate  also, 
according  to  some,  with  the  lymphatics,  at  the  origin  of 
these  last ; this  will  be  examined  under  the  absorbent 
system. 


Erectile  Texture. 

Page  33. — The  spleen,  the  corpus  cavernosum,  in- 
stead of  presenting,  like  the  serous  surfaces,  a vascular 


CAPILLARY  SYSTEMS. 


117 


net-work  in  which  the  hlood  oscillates  in  different  direc- 
tions, according  to  the  motion  it  receives,  exhibit  only 
spongy,  cancellated  textures,  whose  nature  is  but  little 
known  in  which  the  blood  appears  often  to  stagnate,  in- 
stead of  moving,’’  &c. 

The  arrangement  of  the  capillary  system  in  these 
spongy  textures  has  been  very  well  described  by  many 
modern  anatomists.  The  corpus  cavernosum  has  been 
the  particular  subject  of  their  researches.  It  might  be 
thought  at  first  view,  that  it  is  a cellular  or  spongy  tex- 
ture infiltrated  with  blood  ; when  it  is  cut  into,  this  fluid 
flows  from  it  and  seems  to  come  out  of  the  small  open 
spaces  and  not  immediately  from  the  vessels.  It  is  this 
which  deceived  Haller  and  the  anatomists  who  followed 
him,  and  made  them  believe  that  the  blood  was  poured 
out  by  the  arteries  in  the  interstices  of  the  laminse  and 
fibres  of  the  corpus  cavernosum,  from  which  it  was  taken 
up  by,  the  veins.*  But  if  on  the  one  hand,  the  arteries 
are  injected,  they  are  seen  to  terminate  by  very  delicate 
ramifications  which  go  precisely  as  in  the  other  parts  ; 
and  by  injecting  the  veins,  on  the  other,  we  easily  per- 
ceive, 1st,  that  they  are  much  dilated  at  their  origin  ; 2d, 
that  the  species  of  enlargements  which  they  occasion 
have  very  numerous  anastomoses,  like  the  capillary  sys- 
tem of  which  they  make  a part.  It  follows  hence  that 
these  vessels  appear,  as  it  were,  filled  with  openings, 
which  makes  them  resemble  meshes  communicatino: 

O 

together.  The  erectile  texture  of  the  corpus  cavernosum 
is  then  formed  of  small  arteries  and  veins  interlaced  like 

* Such  was  the  opinion  of  Bichat  himself,  an  opinion  by  no  means 
admissible,  and  which  is  abundantly  refuted  by  what  is  here  said  of 
the  structure  of  the  corpora  cavernosa. 


IIS 


ADDITIONS  TO  THE 


the  capillaiy  net-work  ; all  the  difference  is  that  here 
the  venous  branches  are  more  developed  and  dilated  in  a 
particular  manner.  These  enlargements  are  so  unlike 
cells,  that  they  are  only  continued  with  the  veins,  and 
the  internal  membrane  of  these  vessels  is  found  in  them. 

Besides,  this  manner  of  describing  the  erectile  texture 
is  not  new  ; Vesalius,  Ingrassias  and  Malpighi  had  seen 
imperfectly  its  true  arrangement.  John  Hunter  has  said 
positively  that  it  was  formed  only  of  vessels.  Duvernoy 
had  the  same  idea  from  the  dissection  of  the  penis  of  the 
elephant.  In  our  time  Mess.  Cuvier,  Ribes  and  others 
in  France,  Mascagni,  Paul  Farnese  and  Moreschi  in 
Italy,  and  Tieddmann  in  Germany  have  perfectly  demon- 
strated this  fact,  both  in  man  and  various  other  animals. 

In  erection,  the  blood  is  accumulated  in  this  texture  as 
Swammerdam  is  convinced ; but  we  know  not  the  cause 
of  it.  Duvernoy  attributed  this  phenomenon  to  a contrac- 
tion of  the  veins.  Others  have  said  that  it  was  owing  to 
the  entrance  of  the  blood  in  greater  quantity  by  the 
arteries ; it  remains  to  be  explained  by  this  hypothesis, 
why  this  afflux  exists.  Some  have  pretended  that  it  was  a 
vital  expansion  of  this  texture,  and  that  the  accumulation 
of  blood  was  only  secondary. 

There  are  some  parts  whose  structure  resembles  that  of 
the  corpus  cavernosum,  or  which  are  susceptible  of  a sort 
of  erection  more  or  less  similar  to  its  own.  This  appears 
to  be  the  case  with  the  spleen  as  to  structure,  and  even 
as  to  phenomena  ; in  fact,  this  viscus  exhibits  a real  mo- 
tion of  expansion  and  contraction,  1st,  in  experiments  ; 
when  in  a living  animal,  the  course  of  the  blood  in  the 
splenic  vein  is  stopped,  the  spleen  swells  ; it  contracts  as 
soon  as  the  circulation  is  reestablished  ; 2d,  in  diseases  ; 
the  paroxysms  of  intermittent  fever  are  accompanied  with 
an  evident  enlargement  of  this  organ,  which  goes  off  when 


CAPILLARY  SYSTEMS. 


119 


the  paroxysm  is  gone ; 3d,  it  appears  that  the  same  thing 
takes  place  during  digestion.  But  it  is  especially  to  the 
spongy  texture  of  the  urethra,  the  corpus  cavernosum  of 
the  clitoris,  the  nipple  and  the  vascular  texture  of  the 
nymphae,  that  the  name  of  erectile  texture  can  be  applied. 
The  motions  of  the  iris  have  been  explained  by  supposing 
it  formed  of  this  texture.  The  lips  exhibit  something 
analogous.  Everywhere,  moreover,  the  arrangement  of 
the  venous  system  seems  to  indicate,  to  a certain  extent, 
the  presence  of  a sort  of  erectile  texture,  as  has  been 
remarked  by  M.  Chaussier.  Injections  show  the  veins 
everywhere  very  evident  at  their  origin,  and  giving  rise 
to  net-works  with  such  fine  meshes  that  they  might  be 
taken  for  the  cells  of  a spongy  texture ; the  fleshy  part 
of  the  fingers  exhibits  this  arrangement  in  an  evident 
manner. 

Capillary  Circulation. 

Page  36. — ‘‘  The  whole  doctrine  of  the  mechanicians 
rested,  as  we  know,  upon  the  great  extent  which  they 
gave  to  the  movements  of  the  heart.” 

What  we  have  said  of  the  venous  circulation  applies 
also  to  that  of  the  capillaries  ; the  experiment  which  we 
have  cited  proves  the  influence  of  the  heart  upon  this  last 
as  upon  the  first.  Further,  if  in  this  experiment,  the 
artery  is  compressed,  the  jet  of  blood  which  comes  from 
the  vein  lessens  and  becomes  less  rapid.  Then  by  sus- 
pending for  a moment  the  action  of  the  heart  in  relation 
to  the  vein,  we  subtract  one  of  the  causes  which  deter- 
mined the  blood  to  flow  out.  Now,  what  are  these 
causes  ? The  same,  nearly,  as  those  which  pi’oduce  the 
capillary  circulation.  Then,  there  are  recognized  as  causes 


120 


ADDITIONS  TO  THE 


of  the  capillary  circulation,  1st,  the  peculiar  action  of  the 
capillary  net-works  ; 2d,  the  action  of  the  heart.  We 
should  never  lose  sight  of  the  fact,  that  the  heart  may 
influence  this  circulation  in  its  own  way. 


MORBID  ANATOBiy  OP  THE  CAPILLARV  SYSTEM. 

I.  Alterations  in  the  external  forms. 

The  capillary  vessels  appear  to  increase  in  size  under 
two  principal  circumstances  ; 1st,  when  the  course  of  the 
blood  is  found  interrupted  in  an  arterial  or  venous  trunk  \ 
2d,  when  this  fluid  is  accumulated  in  a part  from  the  irri- 
tation which  it  has  experienced. 

After  the  ligature  of  the  artery  of  a limb,  there  takes 
place,  as  is  well  known,  very  important  changes  in  the 
circulation  of  this  limb.  All  the  blood  which  passed 
through  the  tied  artery  flows  back  at  first  towards  the 
capillary  extremities  of  the  collateral  branches  situated 
above,  and  thus  arrives,’by  means  of  the  numerous  anas- 
tomoses of  the  capillary  system,  to  the  branches  situated 
below  the  tied  point.  The  circulation  is  then  carried  on 
in  a circumscribed.space,  almost  exclusively  by  the  capil- 
lary vessels,  which  are  dilated  in  proportion.  Injections 
made  upon  the  dead  body  show  at  this  period  an  innume- 
rable quantity  of  these  vessels,  many  of  which  become 
apparent  only  because  the  blood  passes  through  them  in- 
stead of  the  serous  fluids  which  they  contained.  In  the 
living  animal,  this  sudden  passage  of  a great  quantity  of 
blood  through  the  capillary  system  occasions  an  increase 


CAPILLARY  SYSTEMS. 


121 


of  temperature  and  often  even  a redness  of  the  skin,  after- 
wards one  or  more  of  these  vessels  become  considerably 
larger  than  the  others,  which  return  to  their  original  size  ; 
the  phenomena  pointed  out  gradually  disappear.  There 
usually  exists  then  two  or  three  great  collateral  branches 
dilated,  which  reestablish  the  circulation  in  the  limb. 

The  spontaneous  obliteration  of  the  arteries  is  followed, 
like  their  ligature,  by  the  reestablishment  of  the  circula- 
tion by  means  of  anastomoses.  The  same  phenomena 
take  place  in  regard  to  the  veins  ; there  is,  as  for  the  arte- 
ries, an  increase  of  the  capillary  net-works  at  a certain 
period.  It  is  necessary  moreover,  to  distinguish  this 
increase  of  the  capillaries,  from  that  which  takes'  place  in 
the  anastomosing  branches  of  a more  considerable  size, 
and  which  have  been  noticed  elsewhere. 

II.  iterations  in  the  Organization. 

The  capillaries,  unknown  in  their  structure,  are  also 
unknown  in  the  alterations  of  their  texture.  Contusion 
seems  to  weaken  their  parietes ; at  least  they  are  often, 
in  this  case,  enormously  distended  by  the  blood  ; concus- 
sion appears  to  act  in  the  same  way.  The  capillaries  are 
frequently  raptured,  hence  the  various  species  of  ecchy- 
mosis,  sanguineous  infiltration,  &c.  These  vessels,  divid- 
ed in  wounds,  furnish  at  first  blood,  then  venous  fluids, 
and  then  a substance  capable  of  concretion,  v/hich  becomes 
the  base  of  the  cicatrix. 

III.  iterations  in  the  Development. 

Capillary  net-works  are  produced  preternaturally,  1st, 
in  the  production  of  false  membranes;  2d,  in  the  forma- 
tion of  cicatrices.  Stoll  appears  to  have  been  the  first 
who  remarked  that,  in  some  cases,  the  membraneous  lay- 
16 


122 


ADDITIONS  TO  THE 


ers  which  cover  the  inflamed  venous  membranes  contain 
very  evident  vessels  and  are  continued  with  those  of  the 
venous  membrane  itself.  John  Hunter  and  M.  Chaussier 
have  since  made  the  same  observation.  Most  authors 
admit  that  these  vessels  are  only  an  elongation  of 
those  of  the  serous  membrane.  Mr.  Home  thinks 
with  John  Hunter  that  they  are  developed  in  altogether 
another  way  ; according  to  him,  there  is,  1st,  a foi’ma- 
tion  of  small, bladders  containing  only  colourless  or  even 
gaseous  fluids  in  the  beginning  ; 2d,  union  of  these  blad- 
ders and  the  production  of  a vascular  net-work  still  desti- 
tute of  blood  ; 3d,  finally  anastomosing  between  the  ves- 
sels developed  and  those  of  the  inflamed  membrane,  and 
the  entrance  of  the  blood  into  the  first.  Such  appears  to 
be,  in  fact,  the  course  of  nature.  If  we  fill  with  mercury, 
at  hazard,  a false  membrane  which  does  not  appear  to  con- 
tain vessels,  the  metal  is  distributed  regularly  through  it, 
and  takes  the  form  of  ramified  striae,  similar  to  the  rami- 
fications in  leaves ; they  are  the  vessels  of  the  false  mem- 
brane, which  existed  before  communicating  with  those  of 
the  serous  membrane.  These  vessels  exhibit  even  after- 
wards a diameter  greater  than  that  of  the  vessels  of  com- 
munication, and  a peculiar  arrangement  different  from 
theirs,  as  I have  convinced  myself  by  injection. 

It  is  no  doubt  by  an  analogous  mechanism  that  the 
vessels  of  cicatrices  are  produced.  Mr.  Home  and  M. 
Bauer  have  made  microscopical  experiments,  which  sup- 
port this  idea  ; I think  it  so  much  the  more  admissible, 
as  it  accords  perfectly  with  what  we  know  of  the  forma- 
tion of  the  vessels  in  the  natural  development  of  the 
textures. 

We  find  in  a disease  described  by  Bell  under  the  name 
of  aneurism  by  anastomosis , by  Frier  and  the  German 
authors  under  that  telangiectasis,  this  variety  of  form  of 


CAPILLARY  SYSTEMS. 


123 


capillary  syst^  which  constitutes  the  erectile  texture. 
There  is  often  a defect  of  conformation  which  the  infant 
has  at  birth  ; such  are  most  of  those  called  nsevi  materni. 
This  disease  appears  usually  under  the  form  of  a tumour, 
the  extent,  size,  colour,  &c.  of  which  vary.  A whole 
limb  has  been  seen  to  be  the  seat  of  it.  The  texture 
which  forms  these  tumours  resembles  that  of  the  corpus 
cavernosum ; when  injected  by  the  arteries,  it  is  not 
always  filled  ; injections  succeed  much  better  by  the 
veins.  The  most  ample  details,  however,  on  this  subject 
may  be  found  in  the  work  of  Hodgson,  which  has  been 
already  cited. 


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s 


H’'  '.  -v'..-' -s.vvi'.'  •'-.•j;v.,tt4 


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0,, 

yitj'.y.: 


li 


V ' M/.:^-:  - 


S 


ADDITIONS 


TO  THE 


EXHALANT  SYSTEM. 


Arrangement  of  the  Exhalant  Vessels. 

Page  69. — “ Let  us  reject  then  every  opinion  that  dis- 
regards anatomical  observation,  and  let  us  endeavour  by 
this  observation  to  ascertain  what  the  exhalants  are.” 

It  is  evident,  that  if  we  are  confined  to  strict  observa- 
tion, there  are  no  more  reasons  in  favour  of  the  existence 
of  the  exhalant  vessels,  admitted  by  Boerhaave  and  others, 
than  there  is  for  that  of  the  lateral  pores  imagined  by  Mas- 
cagni. It  is  very  true  that  there  exists  white  vessels, 
as  Vieussens  and  Boerhaave,  at  almost  the  same  time, 
thought,  in  this  sense  that  the  blood  passes  colourless 
through  many  capillaries,  which  do  not  become  visible 
until  their  enlargement  permits  the  red  globules  to  enter 


126 


ADDITIONS  TO  THE  EXHALANT  SYSTEM. 


them.  The  existence  of  these  vessels  is  especially  well 
established  by  an  experiment  of  Bleuland  ; this  author 
injected  by  the  arteries  of  the  intestine  two  substances 
differently  coloured,  one  of  which,  the  thinnest,  went 
beyond  the  red  vessels,  into  a net-work  formed  by  vessels 
of  another  order,  which  arise  from  the  arteries  and  termi- 
nate in  the  veins  ; the  coarser  substance,  on  the  contrary, 
filled  the  arteries  and  the  veins  only  as  far  as  their  direct 
communication.  Ruysch  had  admitted  for  a long  time  that 
injections  colour  parts  which  are  not  naturally  coloured. 
It  is  not  correct,  as  has  been  pretended,  that  this  difference 
depends  only  on  the  quantity  of  the  blood  and  not  on 
the  nature  of  this  fluid  ; for,  when  examined  by  a mi- 
croscope, a single  globule  appears  coloured. 

But  these  white  vessels,  as  injections  show,  terminate 
like  the  red  by  continuing  with  the  veins  ; nothing 
proves  that  they  go  further.  What  are  we  taught  in  this 
respect  by  the  fact  of  the  exhalations,  that  of  nutrition 
and  that  of  transudation  by  the  extremities  of  the  arteries 
in  fine  injections  ? That  there  are  openings  at  these 
extremities,  by  which  the  exhaled  fluids,  the  materials  of 
nutrition  and  the  matter  even  of  injection  escape.  But 
are  these  openings  met  with  at  the  point  of  continuation 
of  the  arteries  with  the  veins,  or  are  they  the  free  ex- 
tremities of  an  order  of  vessels  which  extend  beyond  ? 
Here,  as  may  easily  be  conceived,  observation  is  arrested. 


ADDITIONS 


TO  THE 


ABSORBENT  SYSTEM. 


Origin  of  the  Msorhents. 

Page  95. — “ It  is  not  until  they  have  run  a certain 
course,  that  these  vessels  are  cognizable  by  our  senses, 
and  that  we  can  consequently  study  them  in  a general 
manner.”  ^ 

The  following  are  the  only  anatomical  views  we  have 
upon  the  arrangement  of  the  lymphatics  at  their  origin. 

1st.  Cruikshank  says  that  if  we  examine  a small  in- 
testine during  the  process  of  digestion,  we  perceive 
distinctly  on  ks  internal  surface,  the  orifices  of  these 
vessels,  terminated  like  a watering-pot  and  filled  with 
a chylous  matter  which  renders  them  more  visible. 
Hewson,  Bleuland  and  Hedwig  have  made  observations 


12S 


ADDITIONS  TO  THE 


analogous  to  this,  which  contradict,  indeed,  those  of 
Rudolphi  and  Alb  : Meckel. 

2d.  By  injecting  the  surface  of  the  liver,  and  by  after- 
wards making  the  mercury  pass,  by  pressing  with  the 
finger,  into  the  smallest  vessels,  we  shall  soon  see  it,  as 
Mascagni  has  remarked,  come  out  of  these  vessels  by  small 
openings  and  appear  on  the  surface  of  the  serous  mem- 
brane. These  openings,  it  is  true,  may  be  only  inorganic 
pores  or  even  crevices,  and  not  the  natural  orifices  of  the 
absorbent  vessels. 

3d.  We  have  seen,  in  the  liver  and  testicle,  the  mercury 
driven  in  at  the  ductus  choledochus  and  vas  deferens, 
return  by  the  lymphatic  vessels,  which  seem  to  prove 
that  these  last  are  open  on  the  interior  of  these  ducts.  I 
have  myself  had  occasion  to  ascertain  the  correctness  of 
this  fact. 

4th.  As  to  the  continuation  of  the  lymphatics  with 
the  extremities  of  the  arteries,  admitted  by  the  ancients, 
the  fact  is  still  doubtful.  Most  authors  explain  the 
results  of  injections,  by  saying  that  they  do  not  pass  from 
the  arteries  or  the  veins  into  the  absorbent  vessels,  until 
after  being  effused  into  the  surrounding  textures.  Mas- 
cagni admits,  moreover,  that  the  communication  can  be 
established  directly  by  the  orifices  of  the  lymphatic 
vessels  open  on  the  interior  of  the  arteries. 

Venous  Absorption. — Termination  of  the  Absorbents. 

Page  108. — “ Here,  as  in  so  many  other  points, 
physiology  has  need  of  great  light.” — There  are  “ many 
probabilities  against  and  many  in  favour  of  venous  ab- 
sorption.” 


ABSORBENT  SYSTEM. 


129 


Before  the  discovery  of  the  lymphatic  vessels,  the 
veins  were  generally  considered  as  the  only  agents  of 
absorption.  Afterwards  Hunter  and  Cruikshank  deprived 
them  of  this  property,  to  give  it  exclusively  to  the  absor- 
bent vessels.  At  the  present  day,  the  idea  of  the  ancients 
is  in  part  resumed,  brought  forward  with  new  proofs  by 
Meyer,  Messrs.  Magendie,  Ribes  and  other  modern  phy- 
siologists. The  following  is  one  of  the  most  conclusive 
facts.  Insulate  to  a certain  extent  the  artery  and  vein 
of  a limb,  taking  care  to  cut  all  the  other  living  connex- 
ions which  unite  it  to  *the  trunk,  and  then  introduce  a 
poisonous  substance  into  the  cellular  texture,  the  animal 
will  immediately  experience  all  the  symptoms  of  poison- 
ing. Tiedemann  and  Gmelin  have  proved  by  many  ex- 
periments that  all  the  substances  recognizable  by  their 
odour,  colour  or  chemical  composition,  when  taken  into 
the  stomach,  are  found  in  the  blood  of  the  vena  porta 
with  their  peculiar  characters.  It  must  be  admitted  then, 
either  that  the  veins  have  absorbent  orifices  open  upon  all 
the  surfaces,  or  that  they  communicate  soon  after  their 
origin  with  the  absorbent  vessels.  Abernethy  has  observ- 
ed something  similar  to  this  last  arrangement ; he  has  seen 
the  vasa  elFerentia  going  oflf  from  a lymphatic  gland  in 
order  to  go  to  a vein,  and  the  injection  passing  from  the 
first  to  the  second. 


Structure  of  the  Lymphatic  Glands. 

Page  117. — “In  the  interior  of  these  glands,  these 
branches,”  (absorbents,)  “ very  tortuous,  folded  upon 
themselves  in  different  ways,  occupy  a great  part  of  the 
peculiar  texture  of  these  organs  which  many  thought  in 
consequence  were  nothing  but  an  interlacing  of  the  ab- 
17 


13Q 


ADDITIONS  TO  THE 


sorbents  ; an  idea  that  is  not  proved,  since  this  texture 
is  not  yet  well  known.” 

This  idea,  viz.  that  the  lymphatic  glands  are  nothing 
but  the  interlacing  of  the  absorbents,  is  that  of  Mascagni 
who  regards  them  as  entirely  formed  of  vessels.  Gordon 
coincides  in  this  opinion,  which  appears  in  fact  the  most 
probable,  from  the  considerations  we  are  aboutto  offer. 

There  are,  as  may  be  seen,  two  orders  of  lymphatic 
vessels  in  the  glands  of  this  name  ; some  come  to  these 
glands,  tlie  others  go  from  them!  These  are  the  vasa 
afferentia  and  ejferentia  ; they  are  distinguished  by 
their  situation  and  especially  by  the  direction  of  their 
valves  ; those  of  the  first  have  their  loose  edge  nearer 
than  the  other  to  the  gland  ; it  is  the  reverse  in  the 
second.  The  number  of  these  vessels  varies  ; they  are 
found  from  one  to  thirty  on  each  side.  There  are,  in 
general,  fewer  of  the  efferentia  than  the  ujferentia, 
sometimes  as  many,  rarely  more.  In  order  to  see  ad- 
vantageously the  arrangement  of  these  vessels  in  the 
peculiar  substance  of  the  gland,  it  can  be  injected  on  its 
surface  with  mercury,  or  in  its  interior  with  a substance 
capable  of  becoming  solid.  1st.  If  the  surface  be  inject- 
ed, either  through  the  vasa  afferentia  or  efferentia,  it 
exhibits  on  the  one  part,  divisions  ramified  ad  infinitum, 
and  forming,  as  it  has  been  said,  two  opposite  capillary 
systems  ; and  on  the  other,  branches  dilated,  enlarged 
and  anastomosing  a great  number  of  times,  and  forming, 
like  the  preceding,  net-w'orks  intermediate  to  the  two 
orders  of  vessels  and  belonging  to  both.  2d.  The  follow- 
ing arrangement  is  found  in  the  interior  ; the  vessels, 
filled  with  wax,  appear  even  to  communicate  in  two 
ways,  at  first  by  the  capillary  extremities  similar  to  those, 
which,  in  the  sanguineous  system,  terminate  the  arteries 


ABSORBENT  SYSTEM. 


131 


and  commence  the  veins,  and  moreover  by  enlargements 
which  cannot  better  be  compared  than  to  the  analogous 
enlargements  which  surmount  the  veins  in  the  erectile 
textures.  It  is  in  these  enlargements  that  is  contained 
that  whitish,  thick  matter,  which  Bichat  and  Haller  place 
in  peculiar  cells,  and  which  is  found  more  abundant  in 
children. 

All  the  glands  of  any  size  exhibit  in  an  evident  manner 
the  structure  we  have  just  pointed  out ; it  is  distinguished 
even  in  many  of  the  small  ones,  though  it  is  less  ap- 
parent in  them.  There  is  but  very  little  cellular  tex- 
ture in  these  glands,  and  it  is  very  delicate  if  we  except 
the  fibro-cellular  membrane  which  surrounds  them. 
Their  veins  are  in  very  considerable  number,  especially 
in  this  membrane.  Mascagni,  Walter  and  others  have 
not  been  able  to  trace  nerves  in  them. 

Properties  of  the  Msorhents. — Sensible  Organic  Con- 
tractility. 

Page  120. — The  sensible  organic  contractility  is 
then  at  least  doubtful  in  them,  if  it  exists  it  is  very  ob- 
scure and  at  most  to  be  compared  to  that  of  the  dartos 
muscle.” 

Schreger  has  seen  the  absorbents  in  many  experiments, 
contract  under  the  influence  of  irritating  agents.  Not 
only  the  concentrated  acids,  but  also  the  butter  of  anti- 
mony, alkohol  and  hot  water,  which  we  cannot  suspect 
of  aetitig  by  the  horny  hardening,  have  produced  this 
effect.  The  action  of  cold  water  is  often  sufficient  to 
obtain  the  same  result.  Mechanical  irritations  have  been 
followed  by  alternate  contractions  and  dilatations.  Under 
all  these  circumstances,  the  contraction  is  propagated. 


132 


ADDITIONS  TO  THE 


always  beyond  the  point  touched,  to  a certain  extent. 
These  phenomena,  which  are  very  striking  during  life, 
are  also  observed  after  death  ; they  continue  even  more 
than  those  of  muscular  irritability.  If  we  add  to  this 
that  the  thoracic  duct  is  often,  after  death,  broad  and 
flattened,  though  empty,  whilst  during  life  it  is  almost 
always  found  contracted  and  hardly  visible,  we  must 
admit  that  the  lymphatic  vessels  have  a power  of  vital 
contraction  different  from  that  which  they  possess  after 
death.  It  must  be  by  this  power  that  they  contract  and 
empty  themselves  more  or  less  completely  when  opened 
between  two  ligatures  ; and  in  fact  Tiedemann  has  ob- 
served that  this  phenomenon,  very  evident  during  life, 
in  the  thoracic  duct  and  some  other  trunks,  which  then 
empty  themselves  by  a real  jet,  is  very  slight  after  death. 


MORBID  ANATOMY  OF  THE  ABSORBENT  SYSTEM. 

•l 

I.  Mterations  in  the  External  Forms. 

The  absorbents  appear  to  be  able  to  be  dilated  preter- 
naturally.  Some  authors  consider  as  dilatations  of  this 
kind  the  species  of  hydatids  that  are  observed  especially 
on  the  plexus  choroides,  in  which  they  are  arranged  in  a 
line,  united  to  each  other  by  filaments. 

II.  Mterations  in  the  Organization. 

Inflammation  of  the  lymphatic  vessels  is  followed,  like 
that  of  the  veins,  by  suppuration,  albuminous  effusion. 


ABSORBENT  SYSTEiW. 


133 


obliteration,  &c.  It  has  been  already  discussed  as  well 
as  that  of  the  glands.  The  wounds  of  these  parts  heal  in 
general  quite  early  ; it  is  not  known  if  it  be  with  an  ob- 
literation of  the  vessel ; the  cellular  texture  no  doubt 
contributes  much  to  the  process  of  reunion.  This  process 
is  sometimes  very  slow  in  the  glands ; thus  it  is  often 
preferred  to  remove  them  in  operations,  for  fear  that  their 
swelling  would  separate  the  edges  of  the  wound  and  re- 
tard the  progress  of  cicatrization.  Ruptures,  analogous 
to  those  which  take  place  in  the  veins,  have  been  seen  in 
the  absorbents  ; Assalini  and  Th.  Bartholin  relate  examples 
of  them  as  it  respects  the  thoracic  duct. 

The  lymphatic  glands  are  frequently  the  seat  of  the 
transformation  to  bone,  even  at  an  age  not  greatly  ad- 
vanced. Their  ossification  has  commonly  taken  place  in 
one  part  only  of  their  extent.  The  frequency  of  the 
tubercular  disease  of  these  organs  is  known  ; this  is  not 
the  place  to  describe  this  affection. 

III.  Mterations  in  the  Development. 

The  anatomical  varieties  are  very  numerous  in  the 
lymphatic  as  in  the  sanguineous  system,  besides  those 
which  are  purely  accidental  and  which  depend  on  the 
kind  of  death,  the  previous  disease,  &c.  These  varieties 
extend  to  the  principal  trunks  as  well  as  to  the  secondary 
branches,  to  the  glands  as  well  as  to  the  vessels.  Thus 
the  thoracic  duct  is  sometimes  double,  at  least  in  a certain 
part  of  its  course  ; the  two  branches  then  often  unite 
again  and  thus  enclose  a kind  of  islands.  Nothing  is 
more  variable  than  the  terminations  of  this  canal  at  its 
superior  extremity  : it  is  seen  sometimes  single,  some- 
times pouring  the  lymph  by  two  or  even  three  orifices 
into  the  left  sub-clavian  vein,  sometimes  instead  of  open- 


134 


ADDITIONS  TO  THE  ABSORBENT  SYSTEM, 


ing  into  this  vein,  it  goes  to  the  jugular,  the  right  sub- 
clavian, or  sends  a branch  to  the  vena  azygos.  The 
glands  do  not  vary  less  in  their  number  and  situation. 

Inspection  has  not  yet  demonstrated  lymphatic  vessels 
in  the  preternatural  textures,  such  as  cicatrices  ; yet 
absorption  supposes  them  there,  unless  we  prefer  to  have 
recourse  to  that  of  the  veins. 


ADDITIONS 


TO  THE' 


OSSEOUS  SYSTEM. 


Intimate  Structure  of  the  Bones. 

Page  160. — “ Let  us  consider  the  compact  texture  as 
an  assemblage  of  condensed  fibres,  not  separated  by  lay- 
ers, which  we  can  only  consider  as  imaginary.” 

Much  has  been  written  upon  the  intimate  structure  of 
the  bones,  upon  that  of  the  compact  texture  in  particular. 
Malpighi  admits  that  there  are  laminae  and  fibres  in  this 
texture.  Gagliardi  has  described  minutely  the  osseous 
pins  ; there  seems  to  be  some  truth  in  his  opinion,  be- 
cause we  distinguish  in  fact  in  the  bones,  fibres  which  go 
obliquely  through  their  substance.  Albinus,  who  is  fol- 
lowed in  this  by  most  modern  anatomists,  says  that  there 
are  only  fibres  in  the  osseous  texture,  parallel  in  the  long 
bones  and  radiated  in  the  broad  ones.  Finally,  if  we  may 


136 


ADDITIONS  TO  THE 


believe  Scarpa,  there  is  nothing  but  small  spaces  in  the 
compact  substance  of  the  bones  as  in  the  spongy  sub- 
stance. Michel  Medici  has  already  combatted  this  idea 
and  thinks  with  the  ancients  that  it  is  under  the  form  of 
laminas  that  the  osseous  texture  is  arranged. 

By  confining  ourselves  to  the  examination  of  the  facts 
alleged  for  and  against  these  different  opinions,  we  see,  1st, 
that  the  existence  of  the  fibres  is  by  no  means  demon- 
strated by  the  linear  appearance  which  the  osseous  parti- 
cles take  at  their  development ; in  fact,  this  arrangement 
does  not  continue  long ; in  the  broad  bones,  for  example, 
these  pretended  fibres,  which  then  extend  to  the  middle 
of  the  substance  of  the  bone  are  afterwards  changed  to  an 
areolar  texture.  There  are  however  fibres  in  the  bones, 
as  we  see  after  having  deprived  them  of  their  calcareous 
matter.  2d.  We  may  be  convinced  even  that  there  are 
laminas,  by  taking  a long  bone  softened  by  an  acid  and 
macerating  it  in  water ; its  compact  texture  separates  at 
the  end  of  some  time  into  distinct  laminas,  united  by  fibres 
which  pass  obliquely  from  one  to  the  other.  3d.  In  this 
experiment,  the  laminae  often  finally  resolve  into  filaments 
and  the  whole  bone  at  the  same  time  becomes  spongy. 
From  this  last  fact,  and,  from  this,  that  in  many  diseases 
of  the  bones,  the  compact  substance  becomes  spongy,  as 
well  as  from  the  circumstance,  that  it  evidently  takes  this 
appearance  when,  as  Troja  has  done,  a swelling  of  a long 
bone  is  produced  by  introducing  a foreign  body  into  its 
medullary  cavity.  Scarpa  concludes  that  the  areolar  struc- 
ture alone  exists  in  the  bones  of  which  we  have  spoken. 
This  conclusion  is  not  accurate,  since  besides  the  areolae 
or  small  spaces,  maceration  shows  in  the  bones  lamina) 
and  distinct  fibres.  It  is  true  that,  if  this  maceration  be 
very  long  continued,  it  converts  the  fibres  themselves  into 
a substance,  as  it  were  spongy,  into  a kind  of  mucus. 


OSSEOUS  SYSTEM. 


137 


It  would  seem  then  that  it  is  by  having  had  regard 
only  to  a small  number  of  facts  at  a time,  that  each  author 
has  explained,  in  his  own  way,  the  arrangement  of  the 
osseous  particles,  and  that  we  ought  to  admit  in  the  bones 
laminae,  fibres,  and  areolae  or  small  spaces;  some  are  more 
evident  in  the  spongy  texture,  others  are  more  developed 
in  the  compact  substance. 

•Arrangement  of  the  Pores  of  the  Compact  Texture  of 
the  Bones. 

Page  160. — “ Such  is  the  intimate  juxta-position  of  the 
fibres  of  the  compact  texture,  that  they  leave  between 
them  only  pores  hardly  sensible  to  the  naked  eye,  but 
which  become  so  however  with  a glass  and  which  the 
medullary  juice  and  vessels  fill.” 

These  pores  are  in  many  places  real  tubes  which  con- 
tain marrow  and  blood-vessels.  Havers,  Monro,  and, 
latterly,  Howship  have  described  them.  They  are 
of  an  inch  diameter.  Most  of  them  are  parallel  and 
united  by  others  whose  direction  is  transverse  or  oblique 
to  the  first. 

Composition  of  the  Osseous  Texture. 

Page  167. — “Upon  this  point,”  (the  composition  of 
the  bones,)  “ I refer  to  chemical  books,  especially  to  the 
great  work  of  Fourcroy.” 

The  human  bones  contain,  according  to  M.  Berzelius, 
in  100  parts,  1st,  32,17  of  gelatine  and  1,13  of  blood  ves- 
sels ; 2d,  51,04  of  phosphate  of  lime,  11,30  of  carbonate 
of  lime  and  2,00  of  the  fluate  of  lime;  3d,  1,16  of  the 
18 


1S8 


ADDITIONS  TO  THE 


phosphate  of  magnesia;  4th,  1,20  of  soda,  hydro-chlorate 
of  soda  and  of  water. 

This  analysis,  hitherto  the  most  complete,  does  not 
agree  entirely  with  those  of  other  chemists.  Thus, 
Fourcroy  and  Vauquelin  have  recognized  the  existence 
of  the  oxyds  of  iron,  and  magnesia  silex  and  alumina  in 
the  bones ; on  the  contrary,  they  have  not  found  fluoric 
acid  in  them.  Besides,  the  chemical  composition  of  the 
bones  exhibits  many  differences  not  only  according  to 
age,  sex  and  individuals,  but  even  in  the  different  parts 
of  the  body.  The  analysis  of  M.  Berzelius  was  made 
upon  the  femur  of  an  adult.  But  the  teeth  evidently 
contain  much  more  earthy  substance  ; it  even  appears 
that  it  is  so  with  the  petrous  portion  of  the  temporal 
bone.  Various  other  examples  of  this  kind  are  recorded 
in  the  Anatomy  of  Monro,  from  the  new  researches  of 
J.  Davy. 

In  an  anatomical  point  of  view,  the  bones  are  composed 
essentially  of  a peculiar  fibrous  texture  in  the  areolae  or 
small  spaces  of  which  the  calcareous  substance  is  found 
deposited.  It  is  this  texture  that  is  obtained  by  treating 
a bone  with  acids.  The  residuum  of  this  operation  is 
not  a cartilage,  it  has  neither  its  whiteness,  consistence 
nor  composition  ; flexible  like  the  ligaments,  it  very  much 
resembles  the  fibrous  organs,  from  which  it  differs  only  in 
this,  that  ebullition  transforms  it  more  easily  to  gelatine, 
and  that  maceration  softens  it  quicker.  This  texture  con- 
tains all  the  organic  elements  of  the  bone.  We  cannot 
then  consider  it  merely  as  gelatine,  and  say  that  the  bones 
are  only  a mixture  of  this  substance  and  calcareous  mat- 
ter, as  some  authors  have  done.  This  expression  is  so 
much  the  less  proper,  as  the  gelatine  does  not  exist,  as 
far  as  it  appears,  completely  formed  in  the  bones,  no 
more  than  in  the  other  animal  matters,  since  it  always 


OSSEOUS  SYSTEM. 


139 


requires  the  aid  of  ebullition  to  obtain  it.  Besides,  if  we 
boil  glue  and  calcareous  matter,  there  results  from  it  only 
an  unorganized  compound,  brittle  and  very  different  from 
the  osseous  texture. 

Veins  of  the  Diploe. 

Page  168. — ‘‘  The  accompanying  veins  of  these  arte- 
ries” (the  arteries  of  the  spongy  texture)  ‘'can  hardly 
be  seen.” 

Very  large,  but  insulated  veins  exist  in  some  parts  of 
the  texture  of  the  cells.  They  are  contained  in  peculiar 
venous  canals,  which  Hippocrates  pointed  out,  and  which 
have  since  been  very  well  described  and  injected  by  M. 
Fleury.  These  veins  form  very  numerous  anastomoses ; 
they  are  especially  apparent  in  the  diploe  of  the  bones 
of  the  cranium  but  they  are  also  found  in  the  ossa  ilii,  in 
the  substance  of  the  vertebrae  and  in  the  extremities  of 
the  long  bones.  Their  size  is  greater  in  old  people. 


Development  of  the  Osseous  System. 

Page  206. — “ I would  observe  that  the  arteries,  which 
have  so  great  a tendency  to  ossification,  are  not  so  evi- 
dently gelatinous  as  many  other  substances  which  ossify 
much  less  easily,  as  the  tendons  for  example.” 

Duhamel,  J.  Hunter,  Nesbith,  Reichel,  Stenff  and  many 
others  have  made  known  many  interesting  facts  which 
deserve  to  be  recorded  here.  The  natural  development 
of  the  bones  only  will  be  treated  of,  the  preternatural 
belongs  to  morbid  anatomy. 


140 


ADDITIONS  TO  THE 


The  cartilaginous  state  is  not  always  distinct.  The 
bones  of  the  cranium  really  have  no  pre-existing  cartilages. 
W e shall  see  that  it  is  the  same  with  regard  to  the  middle 
of  the  long  bones. 

The  osseous  state  commences  about  the  time  stated  by 
Bichat.  Stenff  has  found  the  first  rudiments  of  it  at 
forty  days.  I have  seen  some  osseous  points  in  embryos, 
of  thirty  days  or  near  that  period.  The  clavicle  and  the 
jaws  appear  first ; then  successively  and  with  some  days 
interval,  the  humerus  and  the  femur,  the  bones  of  the  leg 
and  those  of  the  fore-arm,  the  ribs,  and  vertebrae,  the 
bones  of  the  cranium,  &c.  The  sternum,  the  ossa  wor- 
miana,  the  patella,  and  the  bones  of  the  carpus  are  the 
last  that  are  ossified.  This  order  is  not  however  confined 
to  any  rule  ; thus  all  those,  which  it  has  been  attempted 
to  establish,  are  for  the  most  part  false  in  their  application. 
The  only  one  which  has  any  real  foundation  is,  that  the 
long  bones  generally  precede  the  broad  ones  in  their 
development,  though  there  are  exceptions.  But  as  to 
the  influence  'W’hich  some  authors  have  given  in  this 
respect  to  the  proximity  to  the  heart  and  to  that  of  the 
nervous  system  ; as  to  what  others  say  of  the  more  or  less 
early  development  of  the  bones  according  to  the  degree  of 
importance  of  their  functions  in  man,  or,  as  some  think, 
according  to  their  more  or  less  intimate  connexion  with 
the  phenomena  of  life  in  the  different  classes  of  animals, 
nothing  of  all  this  is  founded  upon  observation. 

Great  changes  take  place  in  a cartilage  which  is  con- 
verted into  bone.  Vascular  tubes,  which  could  not 
before  be  discovered  in  them,  are  developed.  Colourless 
in  the  beginning,  and  irregularly  arranged,  they  are  after- 
wards ramified  like  the  arteries,  and  traversed  with  blood. 
The  colour  of  this  fluid  manifests  itself  by  degrees  ; these 
tubes  however  do  not  appear  to  contain  it  directly  ; the 


OSSEOUS  SYSTEM. 


141 


vessels  of  the  cartilage  injected  seem  rather  merely  to  line 
their  parietes  ; this  kind  of  vascular  membrane,  which 
covers  them,  has  even  been  considered  as  furnished  to 
secrete  the  osseous  substance.  These  tubes  are  very  well 
seen  in  the  short  bones  and  the  extremities  of  the  long 
ones.  The  osseous  points,  the  development  of  which 
follows  closely  that  of  the  vessels,  is  at  first  merely  an 
union  of  filaments  of  extreme  delicacy,  which  it  is  easy  to 
insulate  by  burning  the  cartilage;  a kind  of  flake  formed 
of  the  calcareous  matter  is  then  obtained.  As  the  ossifi- 
cation advances  the  vascular  canals  are  effaced  ; no  more 
traces  of  them  are  found  as  soon  as  the  epiphyses  become 
solid. 

The  action  of  the  blood  vessels  is  then  increased  in  the 
ossification  of  the  cartilages.  But  do  these  last  experience 
any  other  change  in  their  texture  than  that  which  results 
from  the  deposition  of  an  earthy  substance  ? or  is  the  or- 
ganic matter  renewed,  as  some  authors  have  thought  ? It 
is  necessary  in  fact  that  the  cartilage  should  undergo  a 
very  great  change,  if  it  does  not  entirely  disappear,  in 
order  to  become  bone  ; for  it  contains,  as  we  shall  see 
hereafter,  scarcely  any  thing  but  water,  cellular  texture 
and  albumen,  whilst  the  bones  are  formed  of  a fibrous 
texture  united  to  a saline  substance.  There  is  then  a 
very  great  difference  between  the  composition  of  the  first 
and  that  of  the  second,  and  it  cannot  be  said  that  the 
bones  are  merely  cartilages,  with  the  addition  of  calca- 
reous matter.  Whatever  may  be  the  materials  of  ossifi- 
cation, it  is  the  arteries  which  bring  them  and  pour  them 
out,  either  by  exhalant  extremities,  as  Bichat  thinks,  or 
by  lateral  pores,  which  is  the  opinion  of  Walter.  These 
vessels  do  not  perform  the  part,  which  Nesbith,  Reichel 
and  W.  Hunter  attributed  to  them,  of  giving  place  by 
their  ossification  to  that  of  the  cartilage.  The  regular 


142 


ADDITIONS  TO  THE 


lines  which  the  bones  exhibit  in  their  development  and 
which  have  imposed  upon  these  anatomists,  by  no  means 
follow  the  course  of  the  blood  vessels.  We  shall  be  still 
less  tempted  to  admit  the  hypothesis  of  Mascagni,  who, 
regarding  the  cartilages  as  entirely  formed  of  lymphatic 
vessels,  supposes  that  in  their  ossification  these  vessels 
are  merely  filled  with  calcareous  matter. 

In  the  long  bones,  the  first  osseous  point  appears  from 
the  fortieth  to  the  sixtieth  day,  a little  sooner  in  the  cla- 
vicle. The  small  C3dinder  which  it  forms  is  then  the 
only  solid  part  of  the  bone  ; all  the  rest  is  still  mucous. 
It  is  not  until  from  the  sixtieth  to  the  seventieth  day  that 
the  cartilages  of  the  extremities  appear ; when  these  last 
are  ossified,  which  does  not  take  place  till  much  later, 
there  is  formed  between  them  and  the  body  of  the  bone 
vascular  canals  similar  to  those  which  occupy  their  inte- 
rior. There  is  then  this  remarkable  difference  between 
the  bodies  and  extremities  of  the  long  bones,  that  the 
cartilage  cannot  be  distinguished  in  the  first  as  in  the 
second.  In  the  middle,  the  osseous  texture  seems  to  be 
formed  entirel}’^  of  one  piece  on  the  internal  face  of  the 
periosteum  ; this  texture  is  evidently  cartilaginous  in  the 
beginning  at  each  extremity. 

The  ossification  of  the  broad  bones  of  the  cranium 
begins  at  about  two  months  and  a half.  The  osseous 
points  are  at  first  scattered  in  the  thickened  mucous  sub- 
stance which  represents  the  bone  at  this  period.  They 
afterwards  unite  and  take  the  form  of  irregular  net-works ; 
it  is  not  till  later  that  they  have  that  of  osseous  rays,  still 
covered  with  mucous  substances  on  their  two  surfaces. 
These  rays  disappear  when  the  t’wo  compact  laminae  are 
formed  ; they  are  changed  into  the  texture  of  the  cells. 

The  increase  in  length  of  the  long  bones  takes  place 
near  their  extremities  ; the  middle  has  no  part  in  it.  An 


OSSEOUS  SYSTEM. 


143 


experiment,  for  which  we  are  indebted  to  John  Hunter, 
proves  this  ; if  the  body  of  one  of  these,  bones  is  perfo- 
rated in  two  different  places,  and  the  animal  is  killed 
some  time  after,  the  two  opening;s  are  still  at  the  same 
distance  from  each  other,  though  the  bone  may  have 
increased  in  length.  They  would,  on  the  contrary,  be 
further  apart,  if  the  growth  took  place  in  the  whole  extent 
of  the  bone.  Another  fact  confirms  this.  In  the  experi- 
ments with  madder,  the  colour  appears  in  young  animals 
only  in  the  space  which  separates  each  extremity  from 
the  body  of  the  bone  ; the  rest  is  only  red  at  the  surface, 
unless  the  animal  has  been  fed  for  a long  time  with  this 
substance.  Whilst  a cartilaginous  layer  exists  between 
the  body  and  the  extremity,  we  consider  that  the  growth 
must  take  place  at  the  expense  of  this  cartilage.  But 
when  it  is  once  invaded,  it  must  be  admitted  that  there  is 
a deposition  of  osseous  substance  in  this  place,  preceded 
at  most  by  the  mucous  state.  The  growth  in  length  con- 
tinues until  the  epiphyses  are  united  to  the  body  of  the 
bone,  which  takes  place  at  about  the  age  of  twenty-one. 
A delicate  lamina  of  compact  substance  is  at  first  inter- 
posed between  the  body  and  the  extremity  ; this  after- 
wards disappears  and  the  continuity  becomes  perfect. 

The  three  species  of  bones  grow  in  thickness  much 
beyond  the  term  of  their  growth  in  length,  as  has  been 
already  said.  New  layers  are  incessantly  added  to  their 
surface,  as  is  shown  by  the  colour  of  this  surface  from  the 
continued  use  of  madder.  If  the  use  of  this  substance  has 
been  alternately  discontinued  and  resumed,  the  external 
layers  of  the  bone  are  alternately  red  and  white  ; whence 
it  must  be  concluded  that  they  were  formed  during  the 
continuance  of  the  experiment.  The  osseous  substance  is 
produced  there  as  in  the  preceding  case  without  pre-exist- 
ing cartilage,  and  perhaps  by  passing  through  the  mucous 


144 


ADDITIONS  TO  THE 


state  ; but  there  is  no  Interstitial  deposition,  aS  in  com- 
mon nutrition  ; it  is  rather  a sort  of  juxta-position.  This 
does  not  prevent  the  nutrition  from  taking  place  in  the 
bones  the  same  way  as  in  the  other  parts.  The  use 
of  madder  for  a considerable  time,  so  as  to  obtain  the 
effect  noticed  by  Bichat,  is  a proof  of  it.  There  are 
also  cases  of  preternatural  growth,  both  in  length  and 
thickness,  which  appears  to  arise  from  a real  excess  of 
nutrition. 

At  the  same  time  the  bones  increase  on  the  exterior, 
their  internal  cavities  enlarge  ; which  occasions  the 
parietes  of  the  medullary  canal  of  the  long  bones  to  remain 
in  nearly  the  same  proportion  of  thickness,  as  long  as 
their  growth  without  and  their  diminution  within  coun- 
terbalance each  other.  The  bone  gains  on  one  side  what 
it  loses  on  the  other.  It  is  not  the  same  in  old  age.  The 
growth  in  thickness  does  not  continue,  and  the  internal 
dilatation  does  ; there  results  from  it  an  extreme  delicacy 
of  the  parietes  of  the  medullary  cavity.  This  cause  is 
one  of  those  which  render  the  bones  of  old  people  so 
brittle. 

Some  important  changes  take  place  in  the  osseous  sys- 
tem in  old  age.  The  broad  bones  diminish  in  general  in 
thickness.  Their  texture  of  the  cells  disappears  and  the 
laminaj  of  compact  substance,  which  it  kept  separate, 
come  together  ; this  is  what  is  often  seen  in  the  parietal 
prominences,  in  which  it  is  so  much  the  more  striking  as 
these  prominences  are  replaced  by  a depression.  Some- 
times the  broad  bones  seem  to  have  increased  in  size, 
because  their  texture  is,  if  we  may  so  say,  rarefied  ; deli- 
cate laminjB  which  pervade  it,  give  it  this  appearance. 
In  the  short  bones,  the  external  compact  substance  dimi- 
nishes ; the  areolae  of  the  spongy  texture  are  on  the  con- 
trary more  evident.  The  long  bones,  besides  what  they 


OSSEOUS  SYSTEM. 


145 


lose  of  their  thickness,  seem  also  to  experience  a real 
shortening.  Finally,  the  change  of  composition  which 
takes  place  in  the  osseous  texture  takes  from  it  much  of 
its  elasticity.  The  bones  of  young  subjects  are  flexible 
to  a certain  extent ; we  see  that  at  this  age  the  long 
bones  bend  and  the  broad  ones  yield  under  certain  cir- 
cumstances. The  same  causes  will  produce  a fracture  in 
an  adult,  and  for  a stronger  reason  in  an  old  person. 


Second  Dentition  considered  at  the  period  of  Cutting. 

Page  219.—“  The  second  molar”  (of  the  first  denti- 
tion) “ remains,  as  we  have  just  said  ; it  is  the  first  of 
the  great  ones”  (of  the  second  dentition.) 

This  is  an  evident  contradiction,  and  must  have  escap- 
ed Bichat  from  want  of  attention,  or  else  it  is  a typo- 
graphical error.  It  is  said  above  that  the  first  denti- 
tion is  composed  of  twenty-four  teeth,  of  which  four 
molars  in  each  jaw  are  cut  towards  the  end  of  the  second 
year,  and  two  other  molars  towards  the  age  of  four  years. 
It  is  then  these  last,  or  the  third  of  the  first  dentition, 
which  form  in  the  second  the  first  large  ones.  The  new 
small  molars  take  the  place  then  of  two  teeth  of  the  same 
nature,  and  not  one  alone.  All  the  difference  is,  that 
these  new  small  molars  are  much  less  strong  than  the 
teeth  to  which  they  succeed  ; these  resemble  very  much 
the  great  molars. 


19 


146 


ADDITIONS  TO  TJJE 


MORBID  ANATOBIY  OP  THE  OSSEOUS  SYSTEM. 

I.  iterations  in  the  External  Forms. 

Swelling  of  the  bones  is  of  many  species.  1st.  There 
are  tumours  which  seem  to  be  deposited,  as  it  were,  on 
the  surface  of  the  bone,  so  that  this  is  perfectly  sound 
below  ; such  are  most  exostoses.  This  afi'ection  appears 
to  depend,  in  many  cases,  upon  an  inflammation  of  the 
periosteum,  in  consequence  of  which  this  membrane  is 
detached,  and  secretes  from  its  internal  face  a matter 
which  hardens  and  becomes  confounded  with  the  texture 
of  the  bone  ; a sort  of  periostosis  precedes  the  formation 
of  the  osseous  tumour.  This  is  more  or  less  voluminous 
according  to  the  extent  of  the  inflammation.  If  the  in- 
flammation be  circumscribed,  there  results  from  it  what 
are  called  nodes.  These  tumous  are  at  first  very  dis- 
tinct from  the  bone  ; afterwards  maceration  still  detaches 
them  from  it,  and  they  are  seen  holding  to  the  perios- 
teum ; it  is  not  until  a long  time  that  they  appear  to  be 
continued  with  the  osseous  texture  ; it  may  then  be  seen 
by  the  microscope  that  their  vessels  have  not  the  same 
arrangement  as  those  of  the  rest  of  the  bone,  and  do  not 
appear  to  be  an  elongation  of  them.  When  on  the  con- 
trary the  periosteum  is  inflamed  for  a great  extent,  enor- 
mous laminae  are  produced  and  give  rise  to  the  exostosis 
called  lamellated ; the  bone  is  entire  beneath  these 
laminae  as  in  the  other  cases.  2d.  Some  exostoses  have 
their  seat  in  the  bone  itself,  and  are  produced  by  a de- 
velopment or  separation  of  its  most  superficial  laminae, 
3d.  The  whole  bone  is  stretched,  becomes  thinner  and 
is  considerably  dilated  in  spina  ventosa.  4th.  A real 


OSSEOUS  SYSTEM. 


147 


excess  of  nutrition  is  the  cause  of  the  increase  of  size, 
when  there  is  joined  with  it  an  increased  density,  or 
when  the  density  remains  the  same.  This  is  what  is 
seen  in  exostoses  that  resemble  ivory,  and  in  some  cases 
in  which  the  whole  of  the  bone  appears  to  have  increas- 
ed at  once  in  thickness  and  consistence.  To  the  same 
cause  may  be  referred  the  increase  in  length  which  the 
bones  of  scrophulous  individuals  sometimes  undergo,  that 
in  breadth  which  the  hones  of  the  cranium,  of  the  max- 
illary sinus  exhibit,  in  affections  of  these  cavities.  This 
preternatural  growth,  which  takes  place  in  one  or  many 
bones  whilst  the  others  do  not  partake  of  it,  is  not 
effected  by  a mechanism  analogous  to  that  of  the  natural 
development.  There  is  here  an  interstitial  deposition, 
and  not  a formation  of  successive  layers. 

The  increase  in  substance  may  be  confined  to  the  in- 
crease of  the  density  of  the  osseous  texture.  Enostosis 
or  internal  ossification,  in  which  the  cavities  of  the  bones 
are  effaced,  is  an  example  of  this.  The  bones  of  rickety 
subjects  exhibit  an  analogous  phenomenon,  in  the  com- 
pactness which  their  curvatures  acquire  on  tlie  concave 
side.  . 

A state  opposite  to  the  preceding  is  the  species  of 
atrophy  which  this  texture  experiences  w’hen  absorption 
begins  to  destroy  it,  either  on  the  interior,  as  takes  place 
in  old  age,  or  on  the  exterior,  as  has  been  sometimes 
observed.  According  to  Howship,  to  whom  we  are  in- 
debted for  new  researches  upon  the  alterations  of  the 
bony  texture,  the  brittleness  of  the  bones  depends  in 
some  cases,  in  syphilis,  for  example,  upon  an  alteration 
of  this  kind,  a sort  of  internal  absorption  which  transforms 
the  compact  substance  into  a spongy  texture.  This 
author  distinguishes  the  brittleness  which  arises  from 
this  cause  from  that  which  comes  on,  for  example,  from 


14S 


ADDITIONS  TO  THE 


scurvy  and  scrophula.  This  last  is  generally  attributed 
to  a defect  in  the  proportion  of  the  constituent  elements 
of  the  osseous  texture  ; but  there  appears  to  be  besides 
an  alteration  of  the  animal  matter. 

The  mollities  ossium  resembles  brittleness  very  much  ; 
both  of  them  are  often  met  with  in  the  same  bone.  Mol- 
lities is  of  two  kinds.  One  affects  adults  ; the  bones 
which  are  the  seat  of  it  become  soft  and  flexible,  and  are 
bent  by  the  effort  of  the  muscles  alone ; in  the  dead  body, 
the  scalpel  cuts  them  easily.  Desiccation  and  stewing 
show  that  there  is  an  evident  predominance  of  gelatinous 
substance  in  these  bones,  which  is  also  indicated  by  their 
colour  and  appearance.  The  other  species  of  mollities, 
peculiar  to  children,  differs  from  the  preceding  in  many 
respects. 

The  bones,  compressed  by  neighbouring  tumours,  ex- 
perience various  changes  in  their  shape.  These  tumours 
often  also  destroy  them  in  part,  perforate  them  and  wear 
them  out  to  a greater  or  less  extent.  This  happens 
especially  to  those  which  are  agitated  by  a pulsatory 
motion,  such  as  from  aneurisms. 

The  connexions  of  the  bones,  or  the  articulations  are 
the  seat  of  various  affections  which  change  more  or  less 
the  relations  of  the  articular  surfaces.  The  consolidation 
of  the  immoveable  articulations,  luxations  and  anchylosis 
of  the  moveable  articulations,  exhibit  examples  of  them. 
Preternatural  connexions  sometimes  take  place  between 
the  bones,  as  is  seen  in  false  articulations.  Among  these 
last,  some  succeed  to  luxations,  and  deserve  the  name  of 
supplementary  articulations  ; others,  which  are  in 
consequence  of  fractures,  which  are  formed  by  a single 
bone  divided  into  two  fragments,  are  supernumerary 
articulations.  1st.  When  a luxated  bone  has  not  been 
reduced,  it  may  form  for  itself  a new  cavity  in  the  place 


OSSEOUS  SYSTEM. 


149 


it  occupies.  This  cavity  gradually  acquires  a suitable 
depth ; an  edge,  at  first  cartilaginous,  and  afterwards 
osseous,  is  formed  on  its  circumference ; the  cellular 
texture  thickened  around  the  surface  represents  a sort 
of  fibrous  capsule,*  which  contains  a viscid  fluid  a little 
less  unctuous  than  the  synovia.  A fibro-cartilaginous 
periosteum  covers  the  new  articular  cavity.  The  old  one 
is  altered  and  generally  diminishes  in  extent.  2d.  When 
the  two  ends  of  a fractured  bone  do  not  unite,  either  on 
account  of  their  mobility,  or  from  any  other  cause,  the 
new  relations  which  they  contract  resemble  in  some 
measure  an  articulation,  though  in  a less  degree  than  in 
the  preceding  case.  Most  often  in  fact,  the  fragments 
hold  together  only  by  a kind  of  fibrous  intermediate  lines. 
In  some  cases  nevertheless  their  extremities  become  round 
and  are  encrusted  with|  cartilage,  and  a fibrous  capsule 
surrounds  them.  In  some  fractures  of  the  neck  of  the 
femur,  the  inferior  extremity  has  been  seen  to  form  a 
cavity  in  the  superior ; this  case  might  be  confounded 
with  the  separation  of  the  epiphysis. 

II.  Jilterations  in  the  Organization. 

But  little  is  known  of  the  efiects  of  inflammation  upon 
the  osseous  texture.  It  is  certain  however  that  the  bones 
suppurate.  They  exhibit  this  phenomenon  in  caries,  a 
disease  whose  nature  is  still  unknown,  and  which  appears 
to  be  in  many  cases  a real  necrosis.  In  what  is  called 
white  swelling,  and  which  certainly  comprehends  very 
diflerent  aflections,  something  analogous  is  often  seen  in 
the  articular’  extremities.  They  are  then  the  original 

* Bichat  speaks  of  this  capsule  under  the  synovial  system,  to  which 
it  seemed  to  him  to  belong  rather  than  to  the  fibrous  system.  The. 
fact  is  it  has  not  always  the  same  appearance  in  different  cases. 


150 


ADDITIONS  TO  THE 


centre  of  the  disease.  The  spongy  substance  is  at  first 
softened,  penetrated  witli  vessels  and  then  infiltrated  with 
a reddish  serum.  The  bone  afterwards  suppurates,  and 
fistulas  are  formed  in  its  interior,  which  are  directed 
sometimes  towards  the  external  compact  substance,  and 
sometimes  towards  the  articular  cartilage.  In  this  last 
case,  the  cartilage,  till  then  sound,  is  detached  from  the 
bone,  becomes  tliinner  and  is  perforated  with  holes  ; and 
what  proves  that  the  disease  begins  at  the  bone  is,  that 
the  opening  remains  smaller  on  the  free  surface  of  the 
cartilage  than  on  its  adherent  side,  as  has  been  well  seen 
by  Messrs.  Palletta  and  Brodie,  who  have  described  this 
affection,  aiid  as  I have  myself  ascertained. 

Gangrene  of  the  bones  is  necrosis.  It  is  followed  by 
the  same  phenomena  as  that  of  the  soft  parts,  only  it 
requires  a longer  time  for  the  inflammation,  suppuration 
and  separation  of  the  dead  parts,  which  here  take  the 
name  of  seqicestra.  But  this  necrosis  varies  more- 
over from  its  extent,  as  well  as  from  its  seat.  It  is 
usually  the  result  of  the  destruction  of  the  nourishing 
vessels  of  the  bone,  from  the  detachment  of  the  perios- 
teum or  the  destruction  of  the  medullary  membrane. 
When  it  is  the  medullary  membrane  which  is  injured, 
the  necrosis  only  affects  the  internal  laminae  of  the  bone ; 
the  sequestrum  is  then  contained  in  the  medullary  canal, 
and  has  the  thickness  of  the  bone  to  go  through  before 
it  can  be  thrown  off.  But  in  other  cases,  the  periosteum 
is  inflamed  at  the  same  time  and  is  separated  from  the 
bone  ; this  is  then  affected  with  necrosis  in  its  whole 
thickness,  and  there  take  place  all  the  phenomena  de- 
scribed in  the  article  upon  the  medullary  system  ; the 
periosteum  secretes  a new  bone,  which  surrounds  the  dead 
one.  Here  this  membrane  must  have  remained  uninjured, 
ibr  if  jt  were  destroyed  there  would  be  no  regeneration. 


OSSEOUS  SYSTEM. 


151 


It  is  without  cause  that  Scarpa  and  others  have  denied 
this  regeneration,  and  have  pretended  that  what  has  been 
regarded  as  a new  bone  was  always  a part  of  the  old  one, 
dilated  by  inflammation  and  which  the  necrosis  had  spared. 
The  sequestrum  has  precisely  the  form  of  the  old  bone  ; 
all  the  prominences  and  the  most  superficial  depressions 
are  found  in  it ; the  numerous  specimens  of  this  kind 
that  are  in  existence  leave  no  doubt  upon  the  subject. 
What  has  perhaps  imposed  upon  the  authors  we  have 
just  mentioned  is,  that  the  dead  bone  is  worn  on  its 
surface  and  covered  with  inequalities.  The  new  bone  has 
an  irregular  form,  and  resembles  rather  an  exostosis  or 
a kind  of  vegetation,  than  a bone  which  existed  originally. 
Finally,  in  the  broad  bones,  such  as  the  scapula,  this  is 
still  more  striking  ; there  exists  then  two  bones  of  new 
formation,  one  external,  the  other  internal,  and  the  old 
bone  which  is  dead,  is  contained  in  the  space  between 
the  two. 

The  separation  of  the  periosteum  and  the  denudation 
of  the  bones,  which  is  the  result  of  it,  are  not  always 
followed  by  necrosis,  when  they  take  place  only  to  a 
certain  extent.  If  the  bone  has  not  been  much  contused, 
if  the  subject  be  young  and  the  integuments  be  reapplied, 
an  immediate  reunion  is  obtained  by  the  effusion  of  a 
coagulable  matter.  This  matter  exhibits  at  'a  certain 
period,  irregular  osseous  points,  which  have  given  origin 
to  the  belief  in  insensible  exfoliation  ; these  points  are 
afterwards  effaced. 

Solutions  of  continuity  of  tlie  bones,  or  fractures  differ 
according  as  there  is  at  the  same  time  a wound  in  the  soft 
parts,  or  these  parts  still  cover  the  place  of  fracture.  The 
phenomena  are  entirely  different  in  the  two  cases.  It  is 
only  to  fractures  with  denudation  that  must  be  applied  all 
that  has  been  already  said  upon  the  formation  of  callu?. 


152 


ADDITIONS  TO  THE 


In  these  only  arise  the  fleshy  granulations  which  after- 
wards form  the  basis  of  the  cicatrix,  whether  there  has 
been  exfoliation  by  denudation  or  not.  In  the  others, 
there  are  the  three  periods  that  have  been  pointed  out; 
1st,  a period  of  exudation  ; 2d,  a period  of  tumefaction  ; 
3d,  a period  of  reunion. 

First  period.  The  osseous  texture  cannot  be  divided 
without  the  flow  of  blood  from  tbe  open  vessels ; thus 
there  is  effused  at  first  a certain  quantity  of  this  fluid 
between  the  two  fragments  ; this  quantity  is  usually 
inconsiderable,  and  the  blood  stops  of  itself  at  the  end 
of  a short  time.  Another  fluid  succeeds  it ; this  is  of  a 
serous  nature  and  of  a slightly  viscid  consistence.  The 
effused  blood  gradually  loses  its  red  colour.  Reunion  is 
effected  in  the  periosteum,  the  medullary  membrane  and 
in  all  the  other  soft  parts  which  have  suffered  by  the 
effect  of  the  fracture  alone. 

Second  Period.  These  reunited  soft  parts,  the  perios- 
teum in  particular,  inflame,  swell  and  separate  from  the 
bone  ; hence  a tumour  which  is  visible  externally.  This 
tumour  is  in  great  measure  formed  by  a coagulable  sub- 
stance effused  under  the  periosteum  and  between  its  in- 
ternal laminae.  Osseous  points  are  formed  in  this  sub- 
stance and  finally  take  entire  possession  of  it ; the  carti- 
laginous state  is  hardly  sensible,  and  exists  at  tbe  most 
but  in  some  points.  For  the  want  of  periosteum,  the 
cellular  texture  becomes  the  seat  of  this  ossification,  as 
has  been  seen  by  Macdonald.  The  medullary  membrane 
is  also  ossified. 

Third  Period.  Hitherto  scarcely  any  thing  has  been 
done  in  the  bone  itself ; only  the  two  ends  are  found 
joined  externally  by  a sort  of  clasp,  and  internally  by  a 
plug  which  shuts  up  the  medullary  canal.  But  this  union 
has  only  a slight  degree  of  solidity ; and  if  the  bone  be 


OSSEOUS  SYSTEM. 


153 


as^in  subjected  even  to  incoasiderable  efibrts,  the  callus 
will  yield  or  bend,  and  even  break.  The  process  of 
reunion  Is  carried  on  in  the  fragments  themselves  ; the 
intermediate  substance  which  filled  the  space  between 
them,  hitherto  fluid  becomes  gradually  more  consistent,, 
and  is  penetrated  with  vessels  which  are  continued  with 
those  of  the  periosteum  and  even  of  the  bone.  This 
substance  is  not  long  in  being  ossified  ; it  is  not  known 
precisely  in  what  manner,  though  vessels  have  been 
clearly  seen  to  be  developed  in  it.  At  the  same  time 
that  these  phenomena  take  place,  the  external  swelling 
flattens  down.  Afterwards,  the  ossification  of  the  perios- 
teum disappears,  the  medullary  canal  is  reproduced,  and 
things  are  restored  to  the  state  in  which  tliey  were 
before  the  fracture. 

There  is  then  in  the  reunion  of  fractures,  as  in  wounds 
of  the  soft  parts,  a vascular  cicatrix,  formed  nearly  by 
the  same  mechanism.  The  whole  diflerence  consists  in 
the  changes  which  the  surrounding  parts  undergo,  and 
which  give  place  to  the  development  of  a provisional 
bone,  before  the  final  callus  is  formed.  Strike  out  the 
second  period,  and  the  mode  of  reunion  of  fractured 
bones  will  not  differ  sensibly  from  that  of  the  soft  parts. 

It  is  thus  seen  what  should  be  thought  of  the  opinions 
so  various,  which  authors  have  had  upon  the  formation 
of  callus.  Most  are  exclusive  from  having  observed  the 
callus  in  one  period  of  its  development  only.  It  is  thus 
that  Duhamel,  and  after  him  Fougcroux  and  Pelletan, 
have  seen  perfectly  that  the  periosteum  is  ossified  ; but 
they  attributed  to  it  too  much  in  supposing  that  it  was 
this  which  constituted  the  callus.  Now  this  will  not 
appear  astonishing,  when  it  is  known,  that  Duhamel  did 
not  pursue  his  experiments  upon  the  callus,  otherwise  so 
praiseworthy,  beyond  thirty  or  forty  days.  So  Boer- 
20 


V 


154 


ADDITIONS  TO  THE 


haave,  Hallev  and  Dethleef  found  between  the  fragments 
a lymphatic  matter  and  were  satisfied  with  this  observa- 
tion. Almost  in  our  days,  Hunter,  Macdonald  and 
Howship  have  said  that  it  is  the  effused  blood,  the  colour- 
ing matter  of  which  is  absorbed,  which  is  afterwards 
organized  to  give  birth  to  the  callus.  Others  from  the 
example  of  Bordenave,  have  been  deceived  by  what  takes 
place  when  the  fracture  is  in  contact  with  the  air,  and 
liave  thought  that  it  was  the  same  when  the  fragments 
were  not  exposed  ; Bichat  himself  did  not  avoid  this 
errour.  Some,  such  as  Troja  and  Camper,  have  approach- 
ed nearer  the  truth,  by  adopting  a mixed  opinion.  But 
it  is  especially  to  modern  anatomists  that  we  are  indebted 
for  the  knowledge  of  the  facts  which  we  have  stated. 
M.  Dupuytren  was  one  of  the  first  who  observed  these 
facts.  We  are  indebted  to  Messi's.  Breschet  and  Villerme 
for  a very  extensive  work  upon  this  subject. 

There  are  fractures  in  which  no  bony  callus  is  formed, 
but  only  a fibrous  cicatrix  which  unites  the  two  frag- 
ments loosely.  It  is  what  is  seen  especially  in  those 
bones  which,  like  the  patella,  olecranon  process  and  neck 
of  the  femur,  are  very  difficult  to  be  kept  perfectly  fixed. 
The  motions  of  the  fragments  and  their  separation  are  in 
fact  the  sole  causes  of  this  phenomenon,  which  was  for- 
merly considered  as  constant  in  these  bones  and  dependant 
on  their  structure,  and  which  it  has  been  attempted  to 
explain  by  a pretended  dilution  of  the  osseous  juice,  by 
the  absence  of  periosteum,  &c.  The  same  result  is  obtain- 
ed, when  in  a living  animal,  a portion  of  a long  bone  is 
cut  out ; if  the  distance  between  the  two  ends  be  too  great 
for  their  extremities  to  unite  by  becoming  thinner  and 
extending  towards  each  other,  the  callus  is  in  part  fibrous 
or  fibro-cartilaginous.  The  opening  made  by  a trephine 
exhibits  also  this  peculiarity  ; when  it  is  very  broad  the 


OSSEOUS  SYSTEM. 


155 


-cicatrix  is  completed  by  a fibrous  portion.  On  the  con- 
trary, the  reunion  is  immediate,  even  in  bones  which 
were  not  thought  capable  of  it,  when  the  approximation 
of  the  fragments  has  been  exact  for  a proper  time.  I 
have  seen  patellas  thus  united  ; dried  and  soaked  in 
spirits  of  turpentine  for  the  purpose  of  rendering  the 
cicatrix  transparent,  as  it  would  have  done  if  it  were 
fibrous,  they  proved  to  be  osseous  in  every  part.  These 
cases  are  in  truth  very  rare,  because  the  separation  is 
almost  inevitable,  as  it  may  come  on  not  only  at  the 
instant  of  the  fracture,  but  as  long  as  the  intermediate 
substance  has  any  extensibility,  the  callus  itself  may 
sometimes  yield,  and  it  requires  at  least  two  or  three 
months  for  the  callus  to  acquire  complete  solidity,  instead 
of  from  fifty  to  sixty  days  as  is  commonly  thought.  This 
termination  of  the  fractures  is  precisely  analogous  to  what 
takes  place  in  the  long  bones,  when  their  fragments  are 
continually  moved.  There  results  from  it  a kind  of  false 
' articulation. 

The  bones  are  rarely  afiected  with  organic  diseases ; 
this  point  of  their  history  has  been  hitherto  neglected. 
Yet  the  cancer  of  the  bones  has  been  described  under  the 
name  of  osteosarcoma  ; but  much  remains  to  be  done  to 
classify  all  that  has  been  designated  under  this  name. 
Sometimes  a tubercular  affection  is  met  with  in  the  bones. 
They  are  also  the  seat  of  a kind  of  fleshy  tumour,  which 
interrupts  entirely  their  continuity,  and  the  texture  of 
which  is  very  like  that  of  the  cerebriform  tumours,  ex- 
cept that  it  contains  more  blood-vessels.  J have  many 
times  seen  these  tumours  in  the  clavicle. 

III.  Mterations  in  the  Development. 

The  osseous  system  is  subject  to  frequent  defects  of 
conformation  ; they  are  observed  especially  in  the  bones 
of  the  cranium  and  in  the  sternum. 


156 


ADDITIONS  TO  THE  OSSEOUS  SYSTEM. 


The  osseous  substance  has  a tendency  to  be  produced 
under  many  circumstances.  There  is  scarcely  any  part 
Avhich  is  not  ossified  by  the  progress  of  age.  The  carti- 
lages are  in  the  first  rank  ; then  come  the  fibro-cartilages 
and  tlic  fibrous  textures  as  it  respects  the  frequency  of 
this  ossification.  The  cellular  texture  is  the  most  rarely 
the  seat  of  it.  As  to  the  arteries,  there  is  in  many  cases 
a sort  of  incrustation,  rather  than  a real  osseous  trans- 
formation. The  venous,  muscular  and  nervous  systems 
exhibit  more  rarely  examples  of  it.  The  preternatural 
productions  are  not  exempt  from  this  transformation  ; 
cysts  wholly  osseous  are  often  found.  The  cartilaginous 
state  does  not  seem  always  to  precede  these  ossifications. 


ai^ditions 


TO  THE 


MEDULLARY  SYSTEM. 


Organization  of  the  Medullary  Membrane. 

Page  231. — “ To  be  convinced  of  its  existence/’  (the 
medullary  membrane,)  ‘‘  expose  the  cylinder  that  it  forms 
to  the  intense  action  of  heat ; it  contracts,  has  the  horny 
hardening  immediately  like  all  the  solids,  and  thus  be- 
comes more  apparent.” 

This  experiment  is  made  by  sawing  a long  bone,  and 
then  plunging  it  into  boiling  water  ; the  membrane  sepa- 
rates from  the  bone  and  adheres  to  the  fat,  which  ena- 
bles it- to  be  better  seen.  The  diluted  mineral  acids 
may  also  be  used,  which  produce  the  same  effect. 

This  membrane  when  entirely  detached  from  the  bone, 
resembles  in  some  measure  a cobweb ; it  is  pierced  with 


15S 


ADDITIONS  TO  THE 


a multitude  of  holes.  The  basis  of  it  is  the  cellular  tex- 
ture and  vessels.  The  first  is  in  small  quantity  and  has 
no  other  use  than  to  support  the  vascular  ramifications. 
Among  these  last,  some  which  are  very  well  described  by 
Duverney,  go  outwards  to  the  osseous  texture ; the  others 
go  inwards,  towards  the  elongations  of  this  texture  and 
of  the  membrane  itself.  The  principal  artery  of  the 
medullary  canal  is  surrounded  by  absorbent  vessels  at  its 
entrance  into  this  canal.  An  evident  nervous  plexus  is 
also  observed  about  it,  in  the  bones  which  are  the  nearest 
the  trunk. 

Moreover,  adipose  vesicles  of  the  same  kind  as  those 
of  the  cellular  texture,  though  they  may  be  a little  less 
distinct,  contain  the  medulla  and  occupy  the  interior  of 
the  medullary  membrane,  lodged  in  the  cellular  inter- 
stices which  this  last  contains  ; we  know  not  if  they  are 
also  found  in  the  spongy  texture  of  the  extremities. 
Authors  have  for  a long  time  noticed  that  the  medulla 
is  formed  of  small  grains  united  into  a cluster,  as  is  seen 
especially  when  it  is  recent  and  has  not  yet  lost  the  con- 
sistence which  is  peculiar  to  it.  But  it  was  believed  that 
these  vesicles  communicate  with  each  other,  as  it  was 
then  thought  of  the  adipose  texture.  G.  Hunter,  Mas- 
cagni and  many  others  have  seen  that  they  are  shut.  The 
description  which  they  have  given  of  them,  both  from 
direct  inspection  and  analogy,  shows  in  theta  an  arrange- 
ment similar  to  that  of  the  adipose  texture.  We  shall 
not  advert  again  to  this  arrangement. 

Sensibility  of  the  Medullary  Membrane. 

Page  231. — “ The  most  acute  pains  are  the  result  of 
the  action  of  the  saw  upon  it”  (the  medullary  membrane) 

in  amputation.” 


MEDULLARY  SYSTEM. 


159 


This  phenomenon  is  not  constant ; there  is  often  no 
pain  in  this  case  ; but  we  must  not  conclude  from  it,  as  it 
has  been  done,  that  the  sensibility  of  the  medullary  mem- 
brane does  not  exist.  In  amputations  made  upon  man, 
the  pain  caused  by  the  division  of  the  soft  parts,  and 
especially  of  the  skin,  is  so  intense,  that  this  less  severe 
one  produced  by  the  division  of  the  medullary  membrane, 
which  almost  immediately  succeeds  it,  is  hardly  felt. 
But  if,  in  a living  animal,  the  operation  is  suspended  after 
the  division  of  the  soft  parts,  and  resumed  when  the  first 
impression  is  in  part  dissipated,  the  sensation  is  acutely 
perceived,  and  the  animal  utters  distressing  cries.  The 
sensibility  of  the  marrow,  already  recognized  by  Duverney 
and  since  denied,  is  then  real. 

Development. 

Page  234. — “ This  absence  of  the  medullary  fat  in  the 
foetus,  essentially  distinguishes  the  marrow  from  the  ordi- 
nary fat,  which,  at  this  age,  is  already  very  abundant.” 

The  fat  of  the  bones,  in  being  wanting  in  the  foetus, 
resembles  in  this  respect  that  of  the  deep  parts  in  general, 
which  are  then  almost  entirely  destitute  of  it.  Moreover, 
there  is  not  only  no  marrow  at  this  age,  but  there  is 
no  medullary  membrane.  Bichat  did  not  wish  to  con- 
sider this  membrane  as  a new  organ  ; but  it  is  evident  that 
nothing  indicates  its  presence  before  ossification.  After- 
wards, when  the  medullary  canal  begins  to  be  formed, 
the  nourishing  artery  fills  it  entirely  ; it  is  not  till  an  after 
period  that  this  artery  is  thrown  out  upon  the  parietes  of 
the  cavity  and  that  the  medullary  membrane  exists. 

The  marrow  becomes  very  abundant  in  old  age,  owing 
to  the  enlargement  of  the  medullary  cavity. 


160 


ADDITIONS  TO  THE 


Functions. 

Page  236. — “ Who  does  not  know,  that  in  diseases 
of  the  articulations  in  which  the  synovia  is  altered  and 
vitiated,  the  marrow  of  the  corresponding  bones  is  almost 
always  in  a perfectly  sound  state.” 

To  the  reasons  for  not  admitting  the  production  of  the 
synovia  by  the  transudation  of  the  marrow  through  the 
articular  extremities,  may  be  added  those  which  Soemme- 
ring has  given,  viz.  that  the  marrow  is  the  most  abundant 
precisely  in  the  place  the  most  remote  from  the  extremi- 
ties, and  that  children,  who  have  no  marrow,  and  whose 
extremities  are  all  cartilaginous,  have  not  less  of  synovia 
in  their  articulations.  This  last  fluid  is  met  with  besides 
in  many  places  where  the  other  evidently  cannot  pene- 
trate, as  around  the  tendons,  in  the  bursae  mucosa?,  either 
natural  or  preternatural  ; finally,  there  is  a total  difference 
of  properties  and  composition  between  it  and  the  medul- 
lary fat. 

Various  uses,  not  less  hypothetical,  have  also  been 
attributed  to  the  marrow.  It  has  been  thought  to  be  well 
adapted  to  give  flexibility  and  tenacity  to  the  bones  ; this 
was  the  opinion  of  Duverney  ; but  if  it  be  recollected 
that  the  bones  of  young  subjects  are  the  least  susceptible 
of  breaking,  and  that  those  of  old  people,  which  contain 
so  much  marrow,  are  on  the  contrary  the  least  resisting, 
much  attention  \vill  not  be  paid  to  this  opinion,  which 
rests  only  on  a single  fact ; it  is  this,-  that  the  bones, 
reduced  by  combustion  to  their  calcareous  matter,  resume 
in  part  their  solidity  when  boiled  in  oil  ; but  the  same 
' thing  takes  place  with  every  other  substance,  with  gela- 
tine for  example,  and  there  is  a great  difference  between 


MEDULLARY  SYSTEM. 


161 


a bone  which  combustion  has  destroyed  in  jjart,  and  that 
which  still  contains  all  its  principles. 

The  ancients  said  that  the  marrow  served  to  nourish 
the  osseous  texture  ; but  it  is  sufficient,  that  there  are  a 
great  number  of  bones  destitute  of  medullary  fat,  to  ren- 
der this  inadmissible.  The  medullary  membrane  per- 
forms on  the  interior  of  the  bone  the  office  of  periosteum  ; 
it  contains  nourishing  vessels,  and  it  is  in  this  way  only 
that  it  contributes  to  nutrition.  As  to  the  marrow,  it 
must  have  the  same  general  uses  as  the  fat ; it  is  a kind 
of  aliment  in  reserve,  one  of  the  forms  in  which  the 
nutritive  matter  is  clothed.  It  serves  besides  to  fill  the 
void  which  without  it  would  exist  in  the  medullary  canal. 

Morbid  Anatomy  of  the  Medullary  System. 

The  alterations  of  this  system  have  not  been  sufficiently 
studied  to  enable  us  to  present  a complete  view  of  them. 
We  shall  here  confine  ourselves  to  a mere  sketch. 

It  is  very  probable,  as  Bichat  says,  that  the  medullary 
membrane  of  the  long  bones  is  affected  in  syphilitic  pains. 
In  fact,  a slight  percussion  made  on  the  surface  of  the 
bone  excites  these  pains,  on  account  of  the  jar  it  commu- 
nicates to  the  marrow.  Besides,  we  are  completely  igno- 
rant what  kind  of  alteration  this  last  experiences. 

In  amputations,  the  oily  matter  of  the  bones  is  absorbed 
in  the  neighbourhood  of  the  wound  ; the  medullary  mem- 
brane is  covered  with  fleshy  granulations,  and  contributes 
to  the  formation  of  the  cicatrix.  What  takes  place  after 
fractures  has  already  been  noticed  ; a sort  of  hardened 
plug  fills  the  medullary  canal  ; this  canal  is  afterwards 
reestablished,  unless  the  union  between  the  fragments  be 
not  exact,  as  when  they  slide  over  each  other.  In  necro- 
ses which  include  the  medullary  canal,  when  the  old  bone 
21 


a 62  ADDITIONS  TO  THE  MEDULLARY  SYSTEM. 


has  been  drawn  out,  there  remains  a reddish  membrane 
which  lines  the  new  one  ; but  the  marrow  is  not  repro- 
duced. 

Spina  ventosa  is  an  affection  peculiar  to  the  marrow  ; 
it  is  a true  cancer  of  the  medullary  membrane,  different 
from  the  cancer  of  the  bone  and  from  that  which  affects 
the  periosteum,  but  analogous  to  these  affections  in  its 
nature.  The  disease  has  its  seat  usually  near  the  extrem- 
ities ; on  the  leg,  it  is  towards  the  superior  end,  and  on 
the  thigh,  it  is  towards  the  inferior,  that  it  most  often 
exists.  It  may  happen  that  the  osseous  texture  is  at  the 
same  time  altered  ; but  frequently  this  texture  is  sound 
and  has  only  experienced  a greater  or  less  dilatation,  a 
simple  extension.  It  is  then  found  that  the  bone  forms  a 
covering  to  the  tumour,  sometimes  enormously  dilated, 
often  perforated  and  traversed  by  vegetations  of  a cancer- 
ous nature  ; this  is  what  I have  many  times  had  occasion 
to  observe. 

The  medullary  fat  varies  much  in  quantity  according 
to  the  state  of  corpulency  ; but  tbe  medullary  canal  is 
always  full  of  a fluid  which  resembles  tbe  marrow  more 
or  less.  In  fat  subjects,  the  marrow  has  appeared  to  me 
to  contain,  in  eight  parts,  seven  of  oily  and  one  of  foreign 
matter.  This  agrees  with  what  has  been  stated  by  Gru- 
tozmacher.  In  a phthisical  subject,  I have  seen  the  fat 
form  only  a quarter  ; the  rest  was  a serous  or  albuminous 
fluid  similar  to  that  of  which  Bichat  speaks.  It  would 
then  be  possible,  that  in  extreme  emaciation,  there  might 
be  hardly  any  fatty  matter. 


ADDITIONS 


TO  THE 


CARTILAGINOUS  SYSTEM. 


Peculiar  Texture. 

Page  243. — With  a little  attention  we  distinguish” 
(in  this  texture)  “ longitudinal  fibres,  which  are  crossed 
by  transverse  and  oblique  ones.” 

It  is  very  difficult  to  see  these  fibres  distinctly ; every 
thing  appears  to  be  homogeneous  in  a cartilage  cut  through, 
as  Bichat  observes.  The  only  thing  which  denotes  organ- 
ization in  it  is,  that  an  oozing  of  serum  takes  place,- at  the 
end  of  a short  time,  upon  the  divided  surfaces,  which 
indicates  that  there  were  fluids  in  circulation  in  it.  This 
oozing  is  more  abundant  as  the  subject  is  younger. 

Various  facts  seem  to  show  that  there  is  a peculiar  ar- 
rangement in  the  cartilaginous  texture ; on  this  subject 


164 


ADDITIONS  TO  THE 


(.here  are  difierent  opinions.  Diihamel  thought  that  this 
texture  was  composed,  in  the  cartilages  of  ossification,  of 
concentric  laminae  superadded  to  each  other,  from  the 
formation  of  the  successive  osseous  layers  which  his 
experiments  with  madder  had  demonstrated  to  him. 
These  experiments  have  been  noticed  elsewhere  ; we  have 
seen  what  must  be  concluded  from  them  in  relation  to 
the  growth  of  the  bones.  They  in  no  wise  prove  the 
arrangem.ent  of  which  we  are  treating,  since  the  layers 
are  only  formed  on  the  surface  of  the  bone,  when  this  is 
once  completely  developed  ; we  find  neither  plates  nor 
layers  of  any  kind  in  the  pre-existing  cartilage. 

Hunter  and  Delassone  say  that  the  fibres  of  the  carti- 
lages of  the  moveable  articulations  are  perpendicular  for 
the  most  part,  and  implanted  in  the  bones  of  these  articu- 
lations ; they  compare  the  appearance  which  results  from 
it  to  the  texture  of  velvet.  The  greater  facility  with 
which  these  cartilages  break  in  the  direction  of  their 
thickness,  the  perpendicular  direction  of  the  fibres  which 
is  seen  in  them  when  they  are  cut  in  this  direction,  and 
maceration,  which,  if  sufficiently  long  continued,  renders 
these  fibres  distinct,  are,  it  is  said,  the  reasons  upon  which 
this  opinion  is  founded,  which  cannot  be  entirely  rejected  ; 
for  the  structure  which  has  just  been  described  becomes 
sometimes  apparent  in  diseases.  I shall  say  only  in 
regard  to  the  second  fact,  that  the  traces,  which  the 
instrument  employed  to  make  the  section  of  the  cartilage 
leaves,  have  no  doubt  been  taken  for  fibres. 

According  to  Herissant,  the  cartilages  of  the  ribs  are 
fermed  of  laminae  twisted  into  a spiral  form,  and  it  is  to 
this  arrangement  that  they  owe  their  elasticity.  This 
author  cites  maceration  as  a proof  of  what  he  advances. 
His  observations  on  this  subject  require  confirmation. 


CARTILAGINOUS  SYSTEM. 


165 


Finally,  some  appear  to  have  been  deceived  by  the 
changes  which  the  cartilages  undergo  when  they  are  on 
the  point  of  being  ossified.  It  is  thus  that  Mascagni 
admits  in  the  costal  cartilages  laminae  in  the  form  of  rays, 
because  he  has  found  in  the  centre  of 'these  cartilages  a 
sort  of  marrow  separating  these  laminae.  But  they  exist 
only  in  adults  and  in  cartilages  which  have  been  exposed 
to  desiccation ; now,  the  cartilaginous  texture,  taken  at 
this  period,  is  not  perfectly  homogeneous  ; its  exterior, 
more  compact,  dries  quicker  than  the  interior,  and  cannot 
contract,  w’hen  this  still  tends  to  diminish  in  size ; there 
results  from  this,  spaces  which  are  produced  in  the  centre. 
We  ought  also  to  atti’ibute  to  the  commencement  of  ossifi- 
cation, owing  to  the  progress  of  age,  the  reddish  and 
areolar  cavities  which  Morgagni  and  Portal  have  described 
as  inherent  in  the  structure  of  the  cartilages. 

The  membranous  cartilages  of  the  nose  and  the  ear, 
which  will  be  noticed  under  the  fibro-cartilaginous  system, 
have,  according  to  Soemmering,  distinct  little  fibres,  w’hen 
they  have  been  macerated  a month. 

Chemical  Composition, 

Page  244. — “ Ebullition  upon  the  articular  extremi- 
ties, breaks  it,”  (the  cartilaginous  texture,)  “ and  raises 
it  by  layers  which  it  softens,  and  which  finally  it  melts 
almost  completely.” 

The  cartilages  of  the  sutures  are  likewise  dissolved  in 
boiling  water  and  furnish  a sort  of  jelly,  like  the  diarthro- 
dial  cartilages ; all  the  others  resist  ebullition,  and  do  not 
give  out  gelatine  in  this  case  unless  they  contain  osseous 
points.  This  accords  with  what  is  known  at  the  present 
day  of  the  composition  of  the  cartilages.  Haller  thought 


166 


ADDITIONS  TO  THE 


that  they  were  formed  of  water,  gelatine,  and  an  earthy 
substance  ; but  modern  chemists  have  obtained  different 
results.  Mr.  Hatchett  has  found  in  the  cartilages  albu- 
men and  the  phosphate  of  lime.  M.  Chevreul  has  given 
the  analysis  of  the  cartilaginous  bones  of  the  Squalus 
Maximus ; they  contain,  according  to  his  researches, 
mucus,  oil,  acetic  acid  and  various  salts.  Finally,  accord- 
ing to  J.  Davy,  there  is  in  the  cartilages  44,5  of  albumen, 
55,0  of  water,  and  0,5  of  the  phosphate  of  lime. 

Moreover,  this  composition  must  var}’  at  the  different 
periods  of  life,  as  well  as  the  proportion  of  the  constituent 
principles.  The  cartilages  of  young  subjects  contain  more 
fluids,  as  may  easily  be  proved  by  drying  them  compara- 
tively with  those  of  an  adult.  They  are  reduced  almost 
to  nothing  in  this  experiment,  whilst  the  second  lose 
much  less  of  their  size.  We  see  besides  in  combustion, 
that  there  is  scarcely  any  ashes  left  of  the  first,  whilst 
the  others  give  an  abundant  earthy  residue. 


MORBID  ANATOMY  OF  THE  CARTILAGINOUS  SYSTEM. 

I.  Mterations  in  the  External  Forms. 

The  articular  cartilages  are  sometimes  swelled  and  soft- 
ened in  white  swellings,  at  other  times  detached  in  part, 
hanging  in  the  articulation,  and  often  destroyed  to  a 
greater  or  less  extent ; this  destruction,  frequent  in  the 
diseases  of  the  articulations,  may  bring  on  anchylosis.  In 
some  cases  the  articular  cartilages  seem  to  have  entirely 
disappeared,  and  there  are  only  found  osseous  surfaces 
like  ivory ; is  the  cartilaginous  texture  ossified  in  this 
case  as  Bichat  says,  or  has  it  been  destroyed?  It  is  difii- 


OARTlLAGIiVOUS  SYSTEM. 


167 


cult  to  determine  this.  These  same  cartilages  exhibit 
frequently  after  rheumatic  affections  and  in  consequence 
of  chronic  engorgements,  species  of  floating  fibres,  loose 
at  their  extremity  ; it  is  these  fibres  which  seem  to  favour 
the  opinion  of  Hunter  and  Delassone  upon  the  structure 
of  the  cartilages.  The  cartilaginous  texture  seems  to  be 
decomposed  in  this  case,  unless  this  alteration  be  regarded 
as  the  result  of  a partial  erosion. 

II.  Mterations  in  the  Organization. 

Inflammation  has  never  been  observed  in  the  cartilages  ; 
in  no  case  are  the  vessels  of  these  parts  coloured  with 
blood  ; white  fluids  alone  appear  to  be  capable  of  accumu- 
lating in  them.  Ulceration  however,  which  does  not 
spare  the  articular  cartilages,  as  we  have  just  seen,  is  a 
proof  that  inflammation  may  be  developed  in  them. 

Denudation  and  wounds,  which  everywhere  else  are 
followed  by  inflammation,  do  not  produce  this  effect  in 
the  cartilages.  When  they  are  laid  bare  in  a wound  of 
the  soft  parts,  this  reunites  by  adhesion  or  by  cicatriza- 
tion, according  as  the  flap  has  been  reapplied  or  not ; 
but  the  cartilaginous  texture  does  not  participate  in  the 
work  of  reunion,  as  J.  Hunter  and  J.  Bell  have  seen  ; it 
remains  insulated,  covered  by  the  cicatrix,  without  in 
any  way  adhering  to  it.  When  an  articulation  is  opened 
in  a living  animal,  the  cartilage  does  not  inflame  nor  red- 
den, whatever  may  be  the  duration  of  its  exposure  to  the 
contact  of  the  air  ; only  if  the  experiment  is  prolonged, 
we  see  the  synovial  membrane,  red  at  first  in  the  other 
part  of  it,  inflame  also  over  the  cartilage,  and  the  redness 
of  this  membrane  extends  gradually  towards  the  centre 
of  the  cartilage.  Yet  broken  cartilages  reunite,  as  Auten- 
rieth  first  discovered  in  the  costal  cartilages.  Different 


16S 


ADDITIONS  TO  THE 


observers,  Messrs.  Magendie,  Lobstein  and  myself  have 
recently  confirmed  this  fact.  But  the  part  of  the  carti- 
lages is  purely  passive  in  this  case.  When  those  of  the 
ribs  are  fractured,  if  the  two  ends  remain  opposite,  an 
osseous  band  is  formed  around  them  and  keeps  them  in 
contact ; if,  as  is  most  common,  the  fragments  have  slid 
upon  each  other,  a band,  at  first  fibrous,  then  cartilaginous 
and  osseous,  holding  to  the  perichondrium,  fills  the  space 
between  them  ; but  in  this  case,  as  in  the  other,  they  are- 
merely  contiguous.  It  is  only  in  old  age,  when  the  car- 
tilages are  upon  the  point  of  ossifying,  that  they  reunite, 
like  the  bones,  by  a true  intermediate  callus. 

Ulcers  of  the  diarthrodial  cartilages  are  sometimes  the 
seat  of  a process  of  separation  which  resembles,  to  a cer- 
tain extent,  that  of  the  wounds  of  the  soft  parts.  There 
is  then  found  cartilaginous  portions  newly  formed  in  the 
place  of  those  which  the  erosion  had  destroyed.  This 
affection  has  been  taken  by  some  for  an  original  defect  of 
conformation  ; it  is  evidently  only  secondary. 

The  osseous  transformation  is  the  only  one  which  the 
cartilages  experience  ; but  they  experience  it  almost 
necessarily  with  age,  and  almost  without  departing  from 
the  natural  order.  Besides,  we  distinguish,  in  this  re- 
spect, two  kinds  of  cartilages  ; one,  merely  temporary, 
becomes  ossified  in  the  first  }mar  ; the  other,  which  con- 
tinues a longer  time,  is  called  permanent,  but  only  in 
relation  to  the  first,  for  the  cartilages  of  this  kind  also 
finally  become  ossified  ; the  cartilages  of  the  moveable 
articulations  are  perhaps  the  only  exception.  But  their 
ossification  does  not  take  place  regularly  nor  at  fixed 
periods,  like  tliat  of  the  temporary  cartilages  ; it  may  be 
dela}'ed  to  a very  advanced  age.  Keil  has  seen  the  costal 
cartilages  not  ossified  in  a man  of  a hundred  and  thirty 
years ; Harvey  has  made  the  same  observation  upon 


CARTILAGINOUS  SYSTEM. 


169 


another  of  a hundred  and  fifty-two.  Besides,  the  mecha- 
nism of  ossification  is  the  same  for  all  the  cartilages. 

III.  Mterations  in  the  Development. 

The  cartilaginous  system  is  subject  to  a small  number 
of  defects  of  conformation  ; the  costal  cartilages  some- 
times exhibit  these  irregularities. 

The  preternatural  development  of  this  system  has 
already  been  noticed  ; we  shall  advert,  in  the  synovial 
system,  to  the  foreign  bodies  of  the  articulations  and  to 
the  true  mechanism  of  their  formation.  The  cartilaginous 
productions  differ,  like  all  the  others,  according  as  the}^ 
appear  to  be  deposited,  as  it  were,  in  the  interstices  of 
the  organs,  or  as  they  are  owing  to  a transformation, 
which  one  of  them  has  undergone.  Insulated  cartila- 
ginous masses  have  been  found  in  various  parts.  More 
often  still  various  organs  become  cartilaginous.  M.  Laen- 
nec  has  met  with  this  transformation  in  the  urethra  ; I 
have  observed  it  in  the  vagina,  in  consequence  of  inver- 
sion of  the  womb  ; I have  also  seen  it  in  the  prepuce,  ip 
a case  of  phymosis. 


23 


'ifftJeJWv' 


ADDITION'S 


TO  THE 


FIBROUS  SYSTEM 


Yellow  Fibrous  Texture. 

Page  269. — “ They  appear”  (the  ligaments  placed  be- 
tween the  laminae  of  the  vertebrae)  “ to  contain  much  less 
gelatine,  and  to  be  entirely  different  in  their  nature.” 

These  ligaments  belong,  in  fact,  to  a division  of  the 
fibrous  system,  confounded  for  a long  time  with  the  other 
organs  of  the  same  name,  but  which  difiers  from  them  in 
a great  number  of  characters  ; I shall  now  speak  of  the 
yellow  or  elastic  texture.  It  will  be  necessary  then 
henceforth  to  divide  the  fibrous  system  into  two  great 
classes  ; one  will  comprehend  the  white  fibrous  organs  or 
albugineous  one  of  M.  Chaussier,  the  other  the  yellow 
or  elastic  ones.  The  last  expression  is  perhaps  better 
adapted  than  the  first  to  designate  this  kind  of  texture,  as 
its  elasticity  is  its  principal  character,  whilst  the  colour 


ADDITIONS  TO  THE 


172 

is  not  as  essential  to  it.  Besides,  no  one  that  I know  of, 
lias  given  a complete  description  of  this  texture  ; it  has 
hitherto  only  been  noticed  in  unpublished  lectures.  M. 
Chevreul,  it  is  said,  is  engaged  in  examining  its  compo- 
sition. 

This  texture  is  met  with  wherever  a resistance  is  re- 
quired to  be  continually  in  action,  a sort  of  perpetual 
antagonism,  differing  in  this  respect  from  the  ordinary 
fibrous  texture,  whose  resistance  is,  as  it  were,  passive, 
and  which  is  only  brought  into  exercise  by  distension, 
and  from  the  muscular,  which  only  resists  as  long  as  its 
contraction  continues.  It  is  found  in  animals  under  the 
same  circumstances.  The  posterior  cervical  ligament  of 
quadrupeds  acts  so  as  to  oppose  the  weight,  which  inces- 
santly tends  to  bend  the  head.  A covering  of  the  same 
nature  strengthens  the  abdominal  parietes  in  the  same 
animals,  and  prevents  them  from  yielding  to  the  weight 
of  the  viscera.  The  whole  genus  felts  has  an  elastic 
ligament  inserted  in  the  claw,  keeping  it  extended,  when 
the  animal  no  longer  contracts  its  muscles  to  render  it 
jirominent.  The  shells  of  the  bivalves,  oysters,  muscles, 
&c.  are  opened  by  means  of  an  analogous  fibrous  texture, 
when  the  muscles  which  shut  them  are  relaxed.  In  man, 
besides  the  yellow  ligaments  of  the  vertebras,  we  should 
also  enumerate  among  the  organs  which  this  texture  con- 
ti'ibiites  to  form,  the  peculiar  membrane  of  the  arteries, 
veins,  Ivmphatic  vessels,  excretory  ducts,  air  tubes,  the 
fibrous  covering  of  the  corpus  cavernosum,  the  urethra, 
and  perhaps  also  that  of  the  spleen.  All  these  parts 
require  an  incessantly  active  force,  opposed  to  distension, 
which  makes  them  contract  as  soon  as  the  contrary  effort 
ceases  to  have  the  ascendancy. 

The  filires  of  the  elastic  texture  have  the  same  arrange- 
ment as  those  of  the  white  fibrous  texture.  Their  colour 


FIBROUS  SYSTEM. 


173 


borders  more  or  less  upon  yellow ; it  is  more  evident 
in  the  dead  body.  Their  tenacity  is  less  than  that  of 
the  other  texture  ; their  elasticity,  on  the  contrary,  is 
greater.  The  vessels  of  this  texture  are  few. 

Stewing  does  not  resolve  it  into  gelatine,  like  the  white 
fibrous  texture.  It  appears  to  contain  much  fibrin,  joined 
to  a little  gelatine  and  albumen. 

Its  properties  are  slightly  marked,  except  elasticity 
and  resistance,  which  especially  characterize  it.  It  does 
not  appear  to  be  sensible,  or  at  least  it  is  not  so,  like  the 
fibrous  system  in  general,  except  to  certain  kinds  of  im- 
pressions. It  is  rarely  ossified.  Its  functions  are  to 
serve  as  a connexion  or  covering,  and  to  perform  at  the 
same  time  the  ofiice  of  a spring,  which  obeys  extension 
and  contracts  quickly  when  the  extension  ceases.  This 
is  what  is  very  evident  in  the  arteries;  the  column  of 
blood  which  they  contain,  moved  at  each  contraction  of 
the  ventricles,  stretches  the  parietes  of  these  canals ; but 
the  instant  after,  elasticity  contracts  these  parietes  ; hence 
the  course  of  the  blood  is  continuous,  whereas  it  would 
be  interrupted  if  the  heart  was  the  only  agent  of  impulse,, 
as  we  have  said  elsewhere. 


MORBID  ANATOMV  OF  THE  FIEROFS  SYSTEM. 

I.  Mterations  in  the  External  Forms. 

The  ligaments  and  tendons  become  thick  and  soft  in 
white  swellings  ; they  are  then  brittle,  if  we  may  so 
say^  and  yield  to  the  least  efforts  made  upon  them.  The 


174 


ADDITIONS  TO  THE 


surrounding  cellular  texture  is  often  confounded  with 
them  and  with  that  of  the  neighbouring  parts,  which 
takes  from  them  their  mobility,  and  explains  in  part  the 
immobility  of  their  situation  and  the  embarrassment  of 
the  motions  which  almost  always  accompanies  these  dis- 
eases. In  other  cases,  as  in  some  contractions,  the  mo- 
tions are  prevented  by  the  rigidity  which  the  tendons 
acquire,  and  by  the  difficulty  with  which  they  are  stretch- 
ed. The  ligaments  have  a similar  rigidit}'^  in  false  an- 
chylosis. 

II.  Alterations  in  the  Organization. 

Inflammation  of  the  fibrous  parts  is  but  little  known. 
That  of  the  periosteum  is  the  most  common  ; it  performs 
a very  great  part  in  many  of  the  diseases  of  the  bones. 
I have  seen  several  tendons  the  seat  of  slow  engorgement, 
which  had  sometimes  been  evidently  the  consequence  of 
an  acute  inflammation,  such  as  that  produced  by  a punc- 
ture, for  example.  I have  myself  had  an  affection  of 
this  kind  which  was  produced  by  a puncture  on  the 
hand  ; a tumour  formed  in  the  extensor  tendon  of  a 
finger  and  continued  a very  long  time. 

It  is  particularly  in  ruptures  of  the  tendo  Achillis  that 
we  have  occasion  to  observe  the  mode  of  reunion  of 
the  fibrous  organs  when  divided.  A coagulable  matter 
of  the  nature  of  albumen  or  fibrin  is  then  poured  out, 
which  gradually  increases  in  density,  till  it  finally 
unites  with  solidity  the  two  ends  ; this  substance,  soft 
and  extensible  in  the  beginning,  is  capable  of  being  elon- 
gated at  this  period,  as  happens  in  fact  when  the  limb  is 
too  much  moved.  The  rupture  of  the  ligaments  almost 
always  takes  place  in  luxations  ; but  what  takes  place 
after  the  reduction  of  these  last  has  not  been  described. 


FIBROUS  SYSTEM. 


175 


Ossification  is  rare  in  the  fibrous  texture.  The  kind 
of  hardening  which  this  texture  undergoes  in  old  age 
hardly  ever  extends  so  as  to  produce  this  transformation  ; 
it  scarcely  ever  takes  place  except  in  the  tendons,  at  the 
places  where  there  is  friction,  and  in  the  ligaments,  at 
their  extremity  attached  to  the  bones.  It  is  not  the  same 
in  some  animals  ; in  the  gallinaceous  ones,  for  example, 
the  tendons  of  the  muscles  of  the  feet  are  uniformly 
osseous  at  a certain  period. 

The  periosteum  is  sometimes  affected  with  cancer,  as 
is  seen  in  what  some  call  the  fungus  or  medullary 
fungus  of  the  periosteum,  others  the  bony  tumour, 
lymphatic  tumour  of  the  periosteum,  &c.  Other 
fibrous  organs,  as  the  dura  mater,  exhibit  analogous  tu- 
mours. Periostosis  differs  from  these  tumours  in  this, 
that  it  is  the  effect  of  an  exudation  which  takes  place 
below  the  periosteum  detached  from  the  bone  ; the  matter 
of  this  exudation  becomes  sometimes  more  and  more 
consistent  \ we  have  seen  that  it  may  become  osseous. 

III.  Alterations  in  the  Development. 

Certain  defects  of  conformation  are  accompanied  with 
an  extreme  relaxation  of  the  ligaments  which  unite  the 
bones,  of  which  club-feet  furnish  an  example  ; the  relaxa- 
tion in  this  case  is  but  a secondary  circumstance,  which 
is  owing  to  the  weakness  of  some  of  the  muscles. 

The  fibrous  texture  is  produced  under  many  circum- 
stances. 1st.  Without  speaking  of  its  reproduction 
when  it  is  divided  itself,  the  cicatrices  of  various  organs 
are  essentially  fibrous  ; this  is  what  we  have  already 
seen  under  some  circumstances  in  the  bones,  and  what 
we  shall  see  hereafter  in  the  muscles  and  the  skin.  2d. 
The  cellular  texture,  the  retina,  the  substance  of  the  tes- 


176 


ADDITIONS  TO  THE 


tide  and  the  th3’roid  gland  are  sometimes  changed  int® 
the  fibrous  texture.  3d.  Various  fibrous  productions  are 
developed  in  tbe  substance  of  the  organs.  They  assume 
the  form  of  membranes,  as  in  cysts,  fasciculi,  as  in  the 
ligaments  of  the  false  articulations,  or  they  are  masses 
known  by  the  name  of  fibrous  bodies.  These  bodies 
are  especially  met  with  in  the  uterus  ; Bichat  mentions 
them.  They  occupy  different  points  of  the  substance  of 
this  organ.  Their  number  varies  ; many  are  often  found. 
At  first  very  small,  they  gradually  increase  in  size,  and 
become  in  some  cases  considerably  large.  Their  fibres 
form  laj’crs  nearly  concentric,  and  appear  as  if  wound 
like  balls  ; they  receive  vessels  more  or  less  apparent. 
These  bodies  often  pass  to  the  fibro-cartilaginous  state ; 
but  this  state  is  not  peculiar  to  them,  as  has  been  said. 
Ossification  even  may  seize  upon  them  ; they  then  resem- 
ble stones  or  concretions.  Sometimes  they  are  entirely 
detached  and  fall  off,  either  into  the  cavity  of  the  perios- 
teum, or  into  that  of  the  uterus  ; they  form,  in  the 
second  case,  the  pretended  calculi  of  the  womb,  of  which 
many  examples  are  found  in  a memoir  by  Louis  inserted 
among  those  of  the  Academj"  of  Surgery.  The  fibrous 
bodies  of  the  uterus  have  been  known  for  a very  long 
time  ; Chambon  gave  them  the  name  of  scleroma.  But 
it  is  especially  to  Bichat,  whose  ideas  upon  this  subject 
have  been  published  by  M.  Roux,  and  to  Bayle,  that 
we  are  indebted  for  a more  accurate  description.  Analo- 
gous fibrous  bodies  have  been  found  in  other  parts,  as  in 
the  neck  and  in  the  substance  of  the  fingers.  It  is  not 
unusual  to  find  around  the  vagina,  between  the  bladder 
and  this  canal,  between  the  latter  and  the  rectum,  or  in 
its  parietes  even  fibrous  tumours,  which,  in  truth,  differ 
a little  from  the  preceding.  They  have  not  the  knotty 
appearance  of  these  last ; their  texture,  soft  and  flexible, 


I 


FIBROUS  SYSTEM,  177 

has  some  resemblance  to  that  of  ordinary  polypi.  But 
they  do  not  arise  like  them  ; their  adhesion  to  the  neigh- 
bouring textures  is  slight,  so  that  their  extirpation  is  not 
difficult.  M.  Pelletan  cites  examples  of  this  affection  ; 
M.  Dubois  has  observed  it  a great  number  of  times  ; I 
have  myself  seen  many  of  these  tumours.  Their  structure 
deserves  to  be  examined  thoroughly.  It  is  important  to 
know  them  in  practice,  because  if  care  be  not  taken,  mis- 
takes on  this  subject  may  be  committed. 


23 


>1 

i 


\ 


ADDITIONS 


TO  THE 


FIBRO-CARTILAGmOUS  SYSTEM. 


Of  the  Nature  of  the  Membranous  Fibro-Cartilages. 

Page  316. — “ It  is  not  only  in  its  form,  but  also  in 
its  nature,  that  this  class”  (viz.  that  of  the  membranous 
fibro-cartilages)  “ differs  from  the  others  as  we  shall  see.” 

This  nature  is  perfectly  analogous  to  that  of  the  carti- 
lages, which  the  membranous  fibro-cartilages  resemble  in 
all  their  characters,  as  may  be  easily  seen  by  comparing, 
in  the  history  of  the  fibro-cartilaginous  system,  their  pro- 
perties with  those  of  the  other  bodies  which  are  classed 
under  it.  Thus  Meckel  in  his  General  Anatomy,  observ- 
ing entirely  the  distinction  established  by  Bichat,  between 
this  system  and  the  cartilaginous,  places  these  organs  in 
the  latter  under  the  name  of  membranous  cartilages. 


180 


ADDITIONS  TO  THE 


I am  entirely  of  his  opinion.  In  fact,  1st,  like  the  carti- 
lages, and  the  pretended  membranous  fibro-cartilages  they 
seem  to  be  homogeneous  in  their  structure,  and  have  no 
evident  fibres.  Those  which  cover  this  surface  belong  to 
the  perichondrium,  which  is  very  thick  upon  these  carti- 
lages ; when  stripped  of  this  membrane,  they  have  the 
appearance  of  the  cartilaginous  texture.  2d.  Gelatine 
cannot  be  extracted  from  them  by  ebullition,  as  from  the 
other  fibro-cartilages.  They  are  on  the  contrary  in  this 
respect  like  most  of  the  cartilaginous  textures.  Desicca- 
tion also  acts  upon  them  nearly  as  upon  these  last.  3d. 
Most  of  the  fibro-cartilages  are  destitute  of  perichon- 
drium ; these  have  it  very  distinct,  as  I have  just  said. 
It  is  to  the  fibrous  texture  which  covers  them  that  these 
cartilages  owe  their  suppleness,  the  only  property  which 
they  have  in  common  with  the  fibro-cartilages. 


Of  the  forms  of  the  Fibro-Cartilaginous  System. 

Page  316. — “ These  three  classes  of  fibro-cartilages,” 
(the  membranous,  articular  and  those  of  the  tendinous 
sheaths,)  “ though  very  analogous,  have  not  exactly  the 
same  structure,  the  same  vital  properties,  nor  the  same 
life,  &c.” 

If  the  first  class  be  rejected,  in  conformity  with  what 
has  been  said  above,  there  will  remain  the  articular  fibro- 
cartilages  and  those  of  the  sheaths  of  the  tendons,  which 
are  in  fact  very  different  from  each  other.  These  differ- 
ences appear  to  have  their  source  principally  in  the  differ- 
ent proportions  in  which  the  fibrous  and  cartilaginous 
textures  are  in  this  system  ; whence  results  a more  or 
less  perfect  resemblance  to  one  or  tlie  other  of  these  tex- 


FIBRO-CARTILAGINOUS  SYSTExM. 


181 


tures,  a more  or  less  evident  fibrous  structure,  resistance 
and  flexibility,  or,  on  the  contrary,  more  or  less  elasticity 
and  homogeneousness.  The  following  table  may  be  made 
of  the  fibro-cartilaginous  system,  by  adding  to  the  forms 
pointed  out  by  Bichat,  that  of  the  rings  of  this  nature  in 
which  the  superior  extremity  of  the  radius  and  the  ten- 
don of  the  great  oblique  muscle  of  the  eye  slide,  and  of 
the  bands,  also  fibro-cartilaginous,  which  increase  the 
depth  of  certain  articular  cavities. 


Adherent 
These  are 


3. 


^ ARTICULAR.  fFree  ; example,  that  of  the  lower  jaw. 

They  are  in  re- 
lation with  the  ar- 
ticular surfaces  of 
the  bones,  and  per- 
form various  uses 
towards  them. 

Those  of  the  di-< 
arthrodial  articula-  ' 
tions  are  embrac- 
ed by  the  synovial 
membrane  of  these 
articulations. 

They  may  be  di- 
vided into 

OF  SniDIiVG. 

Their  name  in- 
dicates their  use  ; 
almost  all  are  con-  -{  Circular  ; the  pulley  of  the  great  oblique 
nected  with  the  I muscle  of  the  eye,  and  the  annular  ligament 
tendons.  j of  the  radius;  this  serves  besides  to  close  the 

..  They  are  (^articulation  of  this  bone. 


("  By  their  extremities,  as  that 
of  the  clavicle,  of  the  inferior 
extremity  of  the  ulna,  those  of 
the  knee,  &c. 

By  one  of  their  surfaces,  as 
the  bands  which  are  attached 
to  the  edge  of  the  glenoid,  and 
cotyloid  cavities. 

By  their  two  surfaces  ; such 
are  the  inter-vertebral  sub- 
stances, those  of  the  pubis,  sac- 
l.rum,  &c. 

Flat ; those  of  the  tendinous  sheaths  or  of 
covering. 


182 


ADDITIONS  TO  THE 


3I0RBID  ANATOMY  OF  THE  FIBRO-C ARTILAGINOUS  SYSTEM. 

I.  Jilterations  in  the  External  Forms. 

The  inter-vertebral  substances  are  sometimes  found  in 
diseases  remarkably  swollen,  softened  and  engorged  with 
fluids  ; which  produces  a greater  mobility  and  less  solidi- 
ty in  the  vertebral  column.  The  symphysis  pubis  still 
moi’e  evidently  undergoes  this  alteration  in  pregnancy. 

II.  iterations  in  the  Organization. 

The  organic  aSections  of  the  fibro-cartilages  are  but 
little  known.  Yet  ulcerations  have  been  seen  in  them; 
Messrs.  Palletta  and  Brodie  have  described  a variety  of 
vertebral  diseases  which  commence  by  the  erosion  of 
the  inter -vertebral  fibro-cartilages. 

The  manner  in  which  these  organs  are  repaired  when 
they  are  divided,  has  not  been  ascertained.  It  might  be 
easily  seen,  for  example,  after  the  operation  of  the  divi- 
sion of  the  symphysis  pubis. 

As  to  the  ossification  of  the  fibro-cartilages,  a distinc- 
tion may  be  established  here,  as  in  the  cartilaginous  sys- 
tem, founded  upon  the  period  at  which  this  ossification 
takes  place.  There  are  in  fact,  temporary  fibro-carti- 
lases  which  serve  as  moulds  for  the  bones,  as  there  are 
cartilages  of  this  name  ; these  are  regularly  ossified,  and 
this  transformation  is  for  them  only  a consequence  of  their 
natural  development.  These  fibro-cartilages  of  ossifica- 
tion are  met  with  where  bones  are  developed  in  the 
fibrous  textures,  as  is  seen  in  the  article  on  the  osseous 


FIBRO-CARTILAGINOUS  SYSTEM. 


183 


system,  with  regard  to  the  sesamoid  bones;  the  osseous 
points  of  the  stylo-hyoidean  and  thyro-hyoidean  liga- 
ments are  also  formed  in  this  manner.  On  the  contrary, 
the  permanent  fibro-cartilages  rarely  pass  into  the  osseous 
state.  This  sometimes  happens  as  has  been  said,  with 
regard  to  those  of  the  vertebrae  ; yet  oftentimes  in  these 
cases,  the  external  layers  alone  are  invaded.  At  the 
pubis,  this  phenomenon  is  extremely  rare  ; it  is  a little 
less  so  in  the  sacro-iliac  symphysis  and  in  the  sacral  ar- 
ticulations. The  fibro-cartilaginous  organs  seem  to  be,  in 
this  respect,  intermediate  to  the  cartilaginous  and  fibrous 
textures,  as  they  are  so  in  many  others,  they  are  ossified 
less  often  than  the  first,  but  more  frequently  than  the 
second. 

III.  iterations  in  the  Development. 

There  are  preternatural  fibro-cartilages,  1st,  in  the  cure 
of  some  fractures  badly  kept  in  place  ; 2d,  in  false  ar- 
ticulations, in  consequence  of  w’hich  the  periosteum  often 
takes  this  form  ; 3d,  in  alse  anchyloses,  which  are  some- 
times produced  by  filaments  of  the  same  nature  ; 4th, 
finally,  in  cysts,  in  tumours  of  the  uterus,  the  thyroid 
gland,  &c.  and  in  which  are  often  found  some  fibrous^ 
fibro-cartilaginous  parts,  &c. 


■tnJ 


, * ^jtwK  4*Hr  ■jb^iMAru 

HAmm-.*H[|  " •*»«i  ■•  *■♦»  ■' 

i^fnT'^«ili[MJ(9e»-i^^  - t -•* 

^ et  aMK^^  itnd^v  id'  >•>  - *«m  « 

i met  «kflpsiU/(4.  *.  a !••.«< 

*49^,#  , .o’  ;?< ■ • 


f MU . liM  •_  |iri|Hrt§r  iiki«  , nf  ^ | 


«»t«  ^«ill  ,4\»it«N  Hflmti-  <‘i  M*  • 

|4'  ff  «ff.  Ilia  « i '^lij  - 


- ^ ,.j. »H  <\i  • I - 


?Sj* ^ ■ • - 

^ri-jc  fwuMlwiM'  -jfAJyjV'^' •w«4<Ci^**tf»*4«i»^ 
■4i•^■  ■'-■>'  4t.rCw,o'^>Jx4>iit  .>*i'l  *’rf  .•  ■ * • / 

J.  ,■’  - »Kti^.  x<^mn  ^.n<i;.«<>*tf  111  -<»MrtMn‘  ’ .»^» 

<6i »:  *j  iw<l  |a  >mS* 


^ ' -< 


^\<f^  ^ a 


additions 


TO  THE 


MUSCULAR  SYSTEM  OF  ANIMAL  LIFE. 


Intimate  Structure  of  the  Muscles. 

Page  335. — “ I would  compare  the  anatomical  rcr 
searches  upon  the  intimate  structure  of  the  organs,  to  the 
physiological  researches  upon  the  first  causes  of  the  func- 
tions. In  both  we  are  without  guides,  without  precise 
and  accurate  data ; why  then  give  ourselves  up  to  them  ?” 

Notwithstanding  the  little  apparent  utility  which  these 
researches  seem  to  have,  since  many  learned  men  are  still 
engaged  in  them,  I thought  it  might  be  satisfactory  to  find 
here  a short  analysis  of  the  labours  and  opinions  of  which 
the  muscular  fibre  has  been  the  object. 

Some  consider  it  divisible  almost  ad  infinitum  ; Muys 
says  that  each  fasciculus  must  be  divided  and  subdivided 
eight  times  before  we  can  arrive  at  the  ultimate  muscular 
24 


1S6 


AUDITIONS  TO  THE 


fibre  ; others,  Prochaska  for  example,  think  that  these 
divisions  are  much  too  numerous.  There  is  the  same 
difference  of  opinion  as  to  the  size  of  this  fibre.  It  is 
less,  according  to  most  authors,  than  the  globules  of  the 
blood.  Sprengel,  who  has  measured  it  by  the  micrometer 
of  Banks,  attributes  to  it,  on  the  contrary,  a much  greater 
diameter,  which  he  considers  to  be  equal  to  the  fortieth 
of  a line  in  the  mammalia,  and  to  the  twentieth  in  birds 
and  fishes. 

The  muscular  fibre  appears  to  be  unequal  and  as  it 
were  wrinkled  on  its  surface,  which  has  been  variously 
explained.  It  has  been  said  that  these  inequalities  were 
the  mere  effect  of  muscular  contraction  ; that  they  were 
owing  to  the  contractility  of  texture  of  the  cellular  and 
vascular  parts  which  surround  the  fibre;  that  it  is  a con- 
sequence of  the  knots  and  contractions,  of  which  this  is 
composed.  This  last  opinion  is  best  founded  in  insects, 
which  exhibit  evidently  in  their  fibres  this  kind  of 
knotty  appearance;  but  it  is  not  by  any  means,  so  evi- 
dent in  man.  Meckel,  who  has  seen  this  arrangement 
very  clearly  in  the  first  by  the  microscope,  has  not  been 
able  to  detect  it  in  the  second.  The  muscular  fibre  lias 
appeared  to  him  in  man,  to  be  nearly  uniform  and  of  the 
same  size  in  all  its  points ; only  there  is  always  observed 
in  it  globules  or  opakc  points,  separated  by  a more  trans- 
parent medium  ; which  is  very  different  from  the  knots 
Home  has  also  observed  globules  in  the  muscular  fibre. 
By  examining  this  fibre,  deprived  of  its  cellular  texture 
by  ebullition,  as  it  should  always  be  when  we  would 
study  it  by  itself,  and  by  maceration,  he  has  seen  it  re- 
duced to  round  particles  precisely  similar  to  the  globules 
of  the  blood. 

Various  observers  have  examined  with  the  microscope 
the  transverse  section  of  a muscle.  The  surface  of  this 


MUSCULAR  SYSTEM  OF  ANIMAL  LIFE. 


1S7 


section  resembles  very  much  that  of  basaltic  earth  ; the 
fibres  are  compact,  flattened,  and  prismatic  rather  than 
cylindrical.  A very  good  idea  of  them  may  be  formed 
from  a plate  which  Prochaska  has  given. 

Is  the  muscular  fibre  solid  or  hollow  ? This  is  a ques- 
tion with  which  anatomists  have  been  much  engaged, 
though  it  is  hardly  possible  to  answer  it  b}^  inspection. 
Thus  there  has  been  scarcely  any  thing  but  suppositions 
formed  on  this  subject.  However,  Lecat,  Verheyen  and 
Vieussens  are  all  agreed  upon  this  point,  and  have  be- 
lieved that  it  might  be  concluded  from  their  observations 
that  each  fibre  of  a muscle  was  an  assemblage  of  vessels 
of  a particular  order,  continuous  with  the  arteries  and  the 
veins  at  the  place  where  these  two  orders  of  vessels  are 
confounded,  but  placed  out  of  the  circulation  of  the  latter. 
These  vessels,  which  might  be  called  vessels  of  deriva- 
tion, are  admitted  by  Mascagni ; they  are  the  same  that 
Bleuland  says  he  has  found  in  the  capillary  system  in 
general,  and  in  other  parts  as  well  as  the  muscles.  Hal- 
ler, on  the  other  hand,  rejects  this  opinion.  All  those, 
who  like  him,  divide  the  parts  into  those  that  are  capable 
of  being  injected  and  those  that  are  not,  and  this  is  the 
case  with  the  greatest  number  of  anatomists,  think  that 
the  muscular  fibre  is  solid  and  beyond  the  circulation  of 
the  fluids. 

Influence  of  the  Nerves  upon  Muscular  Irritability . 

Page  384. — “ The  duration  of  this  last  proper!)^,”  (sen- 
sible organic  contractility,)  “ after  the  experiment  I men- 
tioned,” (the  division  of  the  nerves,)  “ proves  completely 
that  the  nerves  are  wholly  foreign  to  it,  that  it  resides 
essentially  in  the  muscular  texture,  that  it  is,  as  Hal-  ^ 
ler  said,  inherent  in  it.  Thus  whilst  in  the  different 


188 


ADDITIONS  TO  THE 


paralyses  the  muscles  lose  the  power  of  obeyiiiEj  the 
cerebral  influence,  or  rather  this  influence  becomes  nothing, 
they  preserve  that  of  contracting  in  an  evident  manner 
when  stimulated.” 

When  all  the  nerves  of  a muscle  are  cut,  the  muscle 
preserves  only  for  a time  the  faculty  of  obeying  the  action 
of  stimuli ; the  contractility  is  soon  exhausted  and  does- 
not  reappear.  On  the  contrary,  when  the  communica- 
tion with  the  nervous  centres  is  free,  the  irritability 
diminishes  also  in  proportion  as  it  is  put  in  exercise,  and 
finally,  as  in  the  preceding  case,  disappears  entirely  ; 
but  if  the  animal  is  suffered  to  rest,  it  is  reproduced. 
Hence  it  would  seem,  that  this  property  is  not  inherent 
in  the  muscle,  but  that  it  is  entirely  subjected  to  the  ner- 
vous influence.  The  duration,  besides  being  shorter,  of 
the  irritability  after  the  division  of  the  nerves  may  very 
well  depend  upon  the  influence  of  these  nerves  below  tbe 
division  ; an  influence  which  can  continue  but  a little 
time,  not  being  renewed,  from  the  want  of  communica- 
tion with  the  nervous  centres.  According  to  this  idea, 
which  is  that  of  Platner,  Legallois,  &c.  the  muscles 
only  put  in  action  a principle  which  is  brought  to  them 
by  the  nerves,  and  these  perform  a double  part  in  the 
contractility  of  the  muscular  texture ; 1st,  they  keep 
this  texture  in  a state  of  constant  excitability  for  the  sen- 
sible organic  contractility  ; 2d,  they  transmit  the  excite- 
ment under  certain  circumstances,  as  it  respects  the  will, 
for  the  animal  contractility.  The  muscles  are  to  the 
nervous  system  what  the  senses  are  to  this  system,  parts 
whose  action  is  intimately  connected  with  its  own,  and 
becomes  nothing  without  it.  And  in  fact  this  action,  in 
the  first  as  in  the  second,  is  exhausted,  lost  and  repro- 
duced nearly  in  the  same  manner.  Sleep,  rest  and  food 


MUSCULAR  SYSTEM  OF  ANIMAL  LIFE. 


189 


reestablish  the  muscular  energy  when  weakened  by  long 
exercise,  as  they  restore  energy  to  the  senses  when  theirs 
has  been  destroyed  by  the  same  cause.  We  have  just 
seen  that  this  does  not  appear  to  apply  solely  to  animal 
contractility,  but  also  to  sensible  organic  contractility, 
or  irritability  properly  so  called. 

However,  all  physiologists  are  far  from  being  agreed 
in  tbe  above  opinion.  A great  number  have  followed 
the  opinion  of  Haller,  and  attributed  to  the  nerves,  no 
other  use  in  contractility,  than  that  of  conducting  the 
stimulus  when  it  comes  from  the  brain.  They  rely  upon 
this,  1st,  that  Tourdes  has  ascertained  that  there  is  mo- 
tion in  pure  fibrin ; 2d,  that  vegetables  and  zoophytes 
contract,  though  they  are  evidently  destitute  of  nerves ; 
and  3d,  that  contractility  is  put  into  action  in  the  muscles 
by  stimuli  which  are  directly  applied  to  them.  But,  1st, 
in  admitting  the  experiment  of  Tourdes,  which  no  one 
since  has  confirmed,  its  results  are  very  different  from 
those  of  muscular  contractility ; 2d,  vegetables  and  ani- 
mals without  nerves  are  also  without  muscles,  thus  their 
contraction  has  nothing  in  common  with  the  latter ; 3d, 
the  last  argument  is  in  part  combatted  by  all  the  reasons 
alleged  above  in  favour  of  the  opposite  opinion.  It  is 
very  difficult,  however,  to  resolve  the  question  in  an 
absolute  manner.  We  find  in  Meckel  a sort  of  mixed 
opinion,  which  is  perhaps  the  most  accurate.  According 
to  this  author,  the  nervous  influence  is  one  of  the  condi- 
tions necessary  to  contraction,  but  it  only  operates  like 
the  blood  which  the  arteries  bring,  being  like  it  indispen- 
sable to  the  life  of  the  muscle,  which  does  notwithstand- 
ing possess  its  irritability  of  itself. 


190 


ADDITIONS  TO  THE 


Quickness  of  the  Muscular  Contractions. 

Page  395. — “ When  it  is  the  will  that  regulates  the 
quickness  of  the  muscular  contractions,  this  quickness 
has  infinitely  various  degrees  ; but  there  is  always  one 
beyond  which  we  cannot  go.” 

This  quickness  is  in  general  very  great ; it  becomes 
sensible  especially  in  the  action  of  playing  upon  different 
instruments ; it  is  found  by  estimating  how  many  differ* 
ent  movements  each  note  of  music  requires  that  there  is, 
in  general,  a contraction  every  sixtieth  of  a second.  Dr. 
Wollaston  has  obtained  the  same  result  in  another  man- 
ner. His  researches  are  given  in  a Croonian  Lecture  pub- 
lished in  the  Philosophical  Transactions  for  the  year 
1810.  The  following  is  the  means  he  adopted  to  mea- 
sure the  quickness  of  the  contractions. 

According  to  his  researches,  muscular  contraction,  how- 
ever short  may  be  its  duration,  is,  as  it  were,  intermit- 
tent, and  composed  of  many  alternate  small  contractions 
and  relaxations ; the  kind  of  buzzing  which  is  heard  in 
the  ear  when  its  aperture  is  closed  by  the  extremity  of 
the  finger,  is  a proof  of  it.  This  peculiar  noise  is  owing, 
according  to  Dr.  Wollaston,  to  the  muscular  effort  which 
the  attitude  requires ; and  in  fact  I have  proved  that  it  is 
nothing  when  the  finger  is  replaced  by  an  inanimate  body. 
Now,  this  buzzing  includes  a sei'ies  of  oscillations  very 
near  together  which  correspond  to  so  many  contractions 
of  the  muscles ; it  was  only  necessary  then  to  find  a term 
of  comparison  for  these  oscillations,  this  Dr.  Wollaston 
has  done.  He  has  compared  this  noise  to  that  which  the 
motion  of  a carriage  produces,  which  is  also  intermittent. 


MUSCULAR  SYSTEM  OF  ANLMAL  LIFE. 


191 


and  the  frequency  of  which  it  is  easy  to  estimate.  He 
has  ascertained  the  quickness  stated  above. 

Size  of  the  Muscles  in  Contraction. 

Page  39S. — “ Their  volume”  ( that  of  the  muscles 
which  contract)  “ remains  about  the  same.  What  they 
lose  in  length  they  nearly  gain  in  thickness.  Is  the  pro- 
portion very  exact  ? Of  what  consequence  to  us  is  this 
insulated  question,  to  which,  since  the  days  of  Glisson, 
so  much  importance  has  been  attached  ! it  deserves  none.” 

There  are  moreover  many  causes  of  error  in  the  ex- 
periments which  have  been  made  on  this  subject.  Swam- 
merdam, for  example,  says  that  by  placing  the  heart  of  a 
frog  in  water  the  fluid  is  seen  to  sink  at  the  moment  of 
contraction  and  to  rise  in  the  relaxation  ; but  the  heart 
containing  a fluid  which  can  increase  or  diminish  the  size 
of  it,  without  any  change  in  the  texture  of  it,  it  is  evi- 
dent that  nothing  can  be  concluded  from  this  experiment. 
So  in  that  of  Glisson,  wdio  immersed  the  arm  of  g man  in 
a tub,  and  afterwards  observed  the  difference  of  the  level 
according  to  the  state  of  contraction  or  relaxation  of  the 
muscles,  the  results  cannot  inspire  great  confidence,  be- 
cause on  the  one  hand,  it  is  quite  diflicult  in  this  case  to 
ascertain  precisely  the  level,  and  because  on  the  other, 
the  contraction  of  the  muscles  being  always  accompanied 
by  the  relaxation  of  the  opposite  muscles,  it  is  impossible 
to  distinguish  these  two  effects  from  each  other. 

One  fact  which  seems  to  offer  something  more  positive, 
was  ascertained  by  Erman.  This  physiologist,  having 
put  a piece  of  an  eel  in  a narrow  tube  of  glass  containing 
water,  saw  at  each  contraction  which  a stream  of  gal- 
vanism produced,  the  water  evidently  sink,  and  rise  again 
during  the  relaxation. 


192 


ADDITIONS  TO  THE 


Besides,  this  question,  with  which  authors  have  been 
much  eng;aged,  has  been  resolved  by  them  in  all  ways. 
Some  have  maintained  that  the  muscle  was  diminished, 
others  have  pretended  that  it  was  increased,  and  finally 
others  have  been  certain,  that  it  was  neither  increased 
nor  diminished  ; it  would  be  difficult  to  imagine  a fourth 
opinion. 

State  of  the  Circulation  in  the  Muscles  during 
Contraction. 

Page  398. — The  blood  contained  in  the  vessels  of  the 
muscles,  especially  in  the  veins,  is  in  part  pressed  out ; the 
increase  of  the  flow  of  blood  by  the  motions  of  the  arm 
in  the  operation  of  bleeding  proves  this  fact.” 

This  fact  is  differently  explained  by  many  physiolo- 
gists, who  admit  that  the  circulation  becomes  more  rapid 
in  a muscle  that  is  in  a state  of  contraction,  and  attribute 
to  this  circumstance  the  increase  of  the  jet  of  blood  by 
the  motions  in  the  operation  of  bleeding.  But  the  greater 
activity  of  the  circulation  during  the  muscular  contrac- 
tion is  far  from  being  rigorously  demonstrated.  Let  us 
see  in  fact  upon  what  this  assertion  rests. 

1st.  It  is  evident  that  the  fact  of  the  bleeding  cannot 
estahlish  this  opinion,  since  we  have  just  seen  that  it  is 
easy  to  account  for  it  without  being  obliged  to  have 
recourse  to  it ; in  fact,  the  muscles  being  increased  in 
thickness  in  their  contraction  must  necessarily  compress 
the  deep-seated  veins,  by  the  resistance  of  the  aponeu- 
roses of  covering,  which  then  perform  the  office  of  a liga- 
ture in  relation  to  these  veins  ; hence  it  is  not  surprising 
that  the  blood  goes  in  greater  quantity  into  the  sub-cuta- 
neous veins. 


MUSCULAR  SYSTEM  OF  ANIMAL  LIFE. 


193 


2d.  The  panting,  which  always  follows  great  motions, 
has  been  cited  ; it  is,  it  is  said,  because  the  circulation  of 
the  blood  through  the  muscles  is  more  rapid,  and  the 
lungs  consequently  receive  it  in  greater  abundance,  that 
respiration  is  accelerated  in  this  case ; thus  the  m.uscles 
which  serve  for  this  function  are  then  in  extreme  activ- 
ity, and  sometimes  finally  become  so  fatigued  that  respi- 
ration can  be  no  longer  supported  by  them,  as  is  seen  in 
animals  pursued  in  the  chase,  who  at  last  fall  down. 
But  it  is  necessary  to  take  into  account  here  a principal 
circumstance,  omitted  in  the  explanation  that  has  been 
given  of  this  phenomenon  ; it  is,  that  the  parietes  of  the 
thorax,  contracted  and  immoveable,  are  to  serve  as  a 
fixed  point  for  the  action  of  all  the  muscles  of  the  body, 
in  all  violent  and  extensive  motions.  Now  this  circum- 
stance explains  all  the  others ; the  circulation  is  more 
rapid,  because  the  vessels  being  compressed  in  the  chest, 
less  blood  can  go  through  them  in  a given  time  ; respi- 
ration is  panting,  because  the  permanent  contraction  of  its 
muscles  impedes  inspiration,  and  it  is  necessary  that  its 
frequency  should  compensate  for  its  want  of  extent ; 
finally  the  muscles  of  inspiration  are  fatigued  by  the  force 
with  which  they  are  compelled  to  resist  all  the  other 
muscles  of  the  body.  The  more  rapid  passage  of  the 
blood  in  the  muscles  is  not  then,  in  this  case,  an  immedi- 
ate consequence  of  their  contraction,  but  is  owing  on  the 
contrary  to  a cause,  which  to  a certain  extent  is  foreign 
to  it. 

From  these  different  considerations,  it  is  evident,  that 
nothing  proves  that  the  circulation  of  the  blood  is  more 
active  in  a muscle  at  the  time  of  its  contraction,  as  has 
however  been  almost  generally  thought.  The  various 
hypotheses,  by  means  of  which  it  has  been  pretended 
that  the  muscular  action  could  be  explained,  have  no 
25 


194 


ADDITIONS  TO  THE 


doubt  given  rise  to  this  idea,  which  could  never  have 
arisen  from  observation,  and  of  which  it  has  been  thought 
that  proofs  were  afterwards  found,  when  the  imagination 
had  once  created  it.  It  is  thus,  that  Prochaska  could 
hardly  refuse  to  admit  it,  when  he  supposed,  very  ingeni- 
ously it  is  true,  that  the  shortening  of  the  muscles  in 
their  contraction  depended  solely  upon  this,  that  the  ves- 
sels placed  transversely  in  the  substance  of  their  fibres, 
suddenly  distended  by  the  fluids  which  entered  them, 
separated  these  fibres  and  made  them  suddenly  fold  up. 

Slate  of  the  Muscles  after  Death. 

Page  419. — “ It  appears  that  these  difierent  states”  (of 
rigidity  or  relaxation)  “ depend  upon  the  kind  of  death, 
upon  the  phenomena  that  accompany  the  last  moments. 
But  how  do  they  precisely  happen  ? It  is  an  object  of 
interesting  research.” 

The  Physiological  Researches  of  Nysten  and  one  of 
the  synoptical  tables  of  Chaussier  may  be  consulted  with 
advantage  upon  this  point.  Muscular  rigidity  is  constant 
after  death  ; it  is  a consequence  of  irritability  ; the  muscles 
are  in  a state  of  real  contraction.  This  phenomenon 
appears  also  to  be  connected  with  the  coagulation  of  the 
blood  ; for  all  the  causes  which  retard  or  promote  the  one 
have  the  same  action  upon  the  other;  a warm  bath,  by  pre- 
serving the  heat  in  a dead  body,  and  by  preventing  the 
coagulation  of  the  fluids,  keeps  up  also  the  suppleness  of 
the  muscles.  But  what  proves  that  cold  is  not  the  sole 
cause  of  the  rigidity,  is  that  this  disappears  after  some 
time,  and  that  the  muscles  are  relaxed  of  themselves 
before  the  period  of  putrefaction.  The  kind  of  death  has 
an  influence  upon  the  duration  of  the  contraction  and  the 


MUSCULAR  SYSTEM  OF  ANIMAL  LIFE. 


195 


time  in  which  it  comes  on.  In  diseases  with  exhaustion, 
such  as  scurvy  and  gangrenous  diseases,  the  rigidity 
appears  very  soon  after  death,  but  soon  gives  way.  On 
the  contrary,  after  acute  diseases  and  sudden  deaths,  it 
does  not  come  on  for  one  or  two  days,  but  continues  a 
much  longer  time  ; it  is  also  greater  in  the  last  case. 
Besides,  the  muscles  are  not  the  only  seat  of  this  rigidity, 
the  cellular  texture  and  the  fibrous  parts  partake  of  it  also. 
The  muscles  of  organic  life  experience  it,  like  the  exter- 
nal muscles,  although  it  is  in  the  latter  that  it  is  particu- 
larly observed. 

Morbid  Anatomy  of  the  Muscular  System  of  Animal 

Life. 

The  alterations  which  the  muscles  of  animal  life  under- 
go will  be  described  with  those  of  the  muscles  of  organic 
life. 


ADDITIONS 


TO  THE 


MUSCULAR  SYSTEM  OF  ORGANIC  LIFE. 


Influence  of  the  Nervous  System  upon  the  Muscles  of 
Organic  Life. 

Page  24,  vol.  3c?. — The  cerebral  and  nervous  influ- 
ence upon  the  organic  muscles  is  not  known  to  us. — It 
is  however  real  to  a certain  extent,  since  it  is  necessary 
that  the  nerves  which  enter  into  the  composition  of  these 
muscles  should  be  of  some  use  ; but  Ave  are  ignorant  of 
this  use.” 

We  have  seen  in  the  muscular  system  of  animal  life, 
that  the  influence  of  the  nerves  upon  the  irritability  of 
this  system  cannot  be  easily  determined.  The  same 
question  recurs  here,  and  is  eA^en  more  complicated.  In 


198 


ADDITIONS  TO  THE 


fact,  in  the  other  system,  there  was  at  least  an  evident 
action  on  the  part  of  the  brain  and  nerves  in  animal  con- 
tractility ; in  this,  this  action  not  only  becomes  doubtful, 
but  the  same  difficulty  exists,  and  even  a greater  one  per- 
haps, in  relation  to  the  part  which  the  nerves  perform  in 
the  organic  contractility.  It  may  be  asked,  1st,  if  the 
brain  has  any  influence  upon  the  contractility  of  the 
muscles  of  organic  life  ; 2d,  if  the  spinal  marrow  be  not 
necessary  to  the  exercise  of  this  contractility  ; 3d,  if  the 
nerves  be  purely  passive  in  this  phenomenon,  so  that  this 
property  is,  according  to  the  expression  of  Haller,  inhe- 
rent in  the  fibre  of  these  muscles. 

The  considerations  offered  by  Bichat  show  that  the 
muscles  of  organic  life  are  independent,  in  their  action,  of 
cerebral  influence  ; but  they  do  not  prove  that  this  cannot 
be  exerted  under  some  circumstances.  Many  of  the  facts 
which  he  has  brought  forward  tend,  on  the  contrary,  to 
demonstrate  this  influence.  The  passions  are  a remarka- 
ble example  of  it.  It  appears  to  me  to  be  extremely  pro- 
bable that,  when  in  a strong  emotion,  for  example,  the 
motions  of  the  heart  are  accelerated,  it  takes  place  only 
because  the  brain  reacts  upon  this  organ  and  transmits  to 
it  the  impression  which  it  has  received.  Placing  the 
primitive  seat  of  the  passions  in  the  organs  of  internal 
life,  is  forgetting,  it  seems  to  me,  that  the  brain  is  the  sole 
organ  of  the  perceptions,  and  that  the  passions  are  always 
the  consequence  of  these  last.  This  however  is  not  the 
place  to  discuss  this  question  ; it  is  sufficient  to  show  that 
the  action  of  the  heart  may  in  this  case  be  entirely  sub- 
jected to  that  of  the  brain.  Those  cases,  rare  ones  indeed, 
in  which  the  will  can  suspend  the  action  of  the  first  of 
these  organs,  seem  to  belong  to  the  same  cause.  Bayle, 
who  possessed  this  singular  faculty,  could  put  it  in  exer- 
cise instantaneously  and  with  the  same  ease  that  he  could 


MUSCULAR  SYSTEM  OF  ORGANIC  LIFE. 


199 


move  a muscle  of  animal  life  ; now,  if  this  depended  on 
the  suspension  of  respiration,  it  would  require  some  time 
for  the  phenomenon  to  take  place.  Aioreover,  the  heart 
is  not  the  only  organ  which  thus  obeys,  in  some  cases,  the 
influence  of  the  brain.  Many  facts  show  that  the  stomach, 
intestines,  bladder  and  even  the  womb  are  also  sensible 
to  this  influence  •,  w*e  know  not,  it  is  true,  if  it  be  by  the 
nerves  that  it  is  transmitted ; but  as  these  agents  are  the 
only  means  of  communication  of  the  brain  with  these 
difierent  organs,  every  thing  leads  to  the  belief  that  such 
is  their  use.  It  must  however  be  acknowledsred  that  we 

O 

want  direct  experiments  in  order  to  place  this  beyond 
doubt.  On  the  contrary,  those  that  have  been  hitherto 
made  teach  us,  that  the  brain  can  be  removed  without 
diminishing  at  all  the  action  of  the  muscles  of  organic  life, 
if  care  be  taken  at  the  same  time  to  support  respiration. 
What  can  we  conclude  from  these  opposite  facts  and  from 
those  stated  by  Bichat } that  no  doubt  the  cerebral  influ- 
ence is  not  absolutely  necessary  to  the  contraction  of  these 
muscles,  but  that  it  can  modify  it  under  certain  circum- 
stances. We  shall  now  see  that  it  is  nearly  the  same 
with  regard  to  the  spinal  marrow. 

On  the  one  hand,  Legallois,  by  numerous  experiments 
which  have  already  been  noticed  in  the  article  upon  the 
nervous  system  of  organic  life,  has  pretended  to  prove 
that  the  heart  receives,  by  the  great  sympathetic,  from 
every  part  of  the  spinal  marrow,  the  principle  of  its 
motion,  which  is  annihilated  when  this  is  wholly  de- 
stroyed ; on  the  other  hand,  various  facts,  which  have  been 
stated  in  this  same  article,  from  the  experiments  of  Clift 
and  Wilson  Philip,  demonstrate  that  often,  notwithstand- 
ing the  absence  of  the  spinal  marrow,  the  heart  continues 
its  action  ; that  some  lesions  of  the  spinal  marrow  have 
more  influence  than  others  upon  this  organ  ; that,  accord- 


200 


ADDITIONS  TO  THE 


ing  te  the  age  and  the  species  of  the  animal,  great  differ- 
ences in  the  results  are  observed,  &c.  Whence  it  is  seen 
that  the  organic  contractility,  though  independent  to  a 
certain  extent  of  the  spinal  marrow,  is  in  some  case 
influenced  by  it. 

Finally,  is  the  continuance  of  this  contractility,  not- 
withstanding the  destruction  of  the  brain  or  spinal  mar- 
row, a proof  that  the  muscular  fibre  is  of  itself  endowed 
with  it,  independent  of  all  nervous  influence,  as  Haller 
thought  ? Certainly  not,  since  the  nerves  exist  and  can 
still  act  insulatedly  in  this  case.  Nothing  is  opposed  to 
our  admitting  here  the  same  hypothesis  as  in  the  muscular 
system  of  animal  life,  viz.  that  the  muscles  derive  from 
the  nervous  system  the  principle  of  their  action  ; but  I 
know  of  no  fact  which  proves  this  in  an  incontestable 
manner. 

Duration  of  the  Organic  Contractility. 

Page  38. — “ This  duration  is  longer  than  that  of  the 
animal  contractility.  When  the  spinal  marrow  is  irritated, 
the  external  muscles  remain  immoveable,  whilst  the  inter- 
nal ones  are  still  in  activity.” 

This  comparison  has  for  its  object  only  the  two  species 
of  contractility,  considered  in  the  two  corresponding  sys- 
tems. But  that  of  animal  life  enjoys  not  only  the  con- 
tractility of  this  name,  but  possesses  also,  according  to  the 
distinction  made  by  Bichat,  organic  contractility.  Now 
this  differs,  as  it  respects  its  duration  after  death,  in  the 
different  muscles  of  the  two  systems. 

Haller,  who  perceived  this  fact,  says  that  it  is  the 
heart  which  remains  the  longest  sensible  to  the  action  of 
stimuli ; that  next  to  it,  the  intestines  are  the  slowest  in 


MUSCULAR  SYSTEM  OF  ORGANIC  LIFE. 


201 


losing  the  faculty  of  contracting  ; that  the  stomach  comes 
next  and  then  the  diaphragm,  and  that  finally  the  exter- 
nal muscles  are  the  first  in  which  this  faculty  is  extin- 
guished. He  adds,  that  in  some  cases,  the  intestines  ap- 
peared to  him  to  preserve  their  irritability  longer  than  the 
heart.  New  researches,  for  which  we  are  indebted  par- 
ticularly to  Nysten,  prove  that  this  order  is  not  in  fact 
exact.  The  kind  of  death,  the  nature  of  the  stimulus  em- 
ployed, &c.  make  the  duration  of  the  irritability  vary  in 
the  different  muscles  ; it  is  thus  that  the  heart  for  a longer 
time  obeys  the  irritation  which  arises  from  a puncture  with 
the  point  of  an  instrument,  whilst  the  voluntary  muscles 
are  longer  sensible  to  the  stimulus  of  Galvanism. 

A numerous  series  of  experiments  has  enabled  Nysten 
to  establish  the  following  order,  which  is  very  different 
from  that  of  Haller;  1st,  the  left  ventricle  of  the  heart, 
which  gives  for  the  shortest  time  signs  of  irritability,  and 
is  tlius  found  at  the  bottom  of  the  scale  ; 2d,  the  large  in- 
testines ; 3d,  the  small  intestines  ; 4th,  the  stomach  ; 5th, 
the  bladder ; 6th,  the  right  ventricle ; 7th,  the  oesopha- 
gus ; 8th,  the  iris,  whose  motions  this  physiologist  has 
also  examined  ; 9th,  the  muscles  of  the  trunk  ; 10th, 
those  of  the  inferior  extremities  ; 11th,  those  of  the  supe- 
rior extremities  ; 12th,  finally,  the  auricles,  the  contrac- 
tility of  which  is  preserved  after  this  property  has  ceased 
in  all  the  other  parts ; it  is  extinguished  in  the  last  place 
in  the  left  auricle,  a fact  very  long  known,  and  which  is 
mentioned  by  Galen. 

Force  of  the  Dilatation  of  the  Muscles. 

Page  54, — “ It  appears  then  very  probable  that  the 
dilatation  of  the  organic  muscles  is  a phenomenon  gs  vital 
as  their  contraction.” 

26 


202 


ADDITIONS  TO  THE 


Without  absolutely  denying  that  the  internal  or  invol- 
untary muscles  can  be  dilated  and  the  voluntary  ones 
elongated,  by  a peculiar  vital  action,  analogous  to  the 
contraction  of  these  same  muscles,  I would  observe  that 
most  of  the  facts  which  tend  to  prove  this  action  can  be 
explained  in  another  way,  and  often  depend  on  causes 
which  are  wholly  foreign  to  it,  and  which  have  been 
overlooked  by  those  who  admit  this  action.  It  is  thus 
that  Barthez  cites  as  phenomena  of  this  kind,  owing  to  a 
sort  of  active  repulsion  opposed  to  the  attraction  which 
predominates  in  the  sliortening  of  the  muscular  fibres,  the 
elongation  of  the  trunk  of  the  elephant,  that  of  reptiles, 
worms,  &c.  in  the  act  of  crawling,  and  even  that  of  the 
tongue.  It  is  evident  that,  in  all  these  cases,  the  elonga- 
tion is  but  a secondary  effect  of  tbe  shortening  of  certain 
muscles,  which  by  their  arrangement,  cannot  produce  it 
except  by  a real  dilatation.  The  leech,  for  example,  has 
longitudinal  fibres,  the  effect  of  which  is  to  shorten  it,  but 
as  it  has  at  the  same  time  circular  fibres  which  cannot  be 
contracted  without  elongating  it,  the  space  which  these 
fibres  enclose  evidently  increasing  in  one  direction, 
whilst  it  diminishes  in  another.  It  is  the  same  with  re- 
gard to  worms,  &c.  The  trunk  of  the  elephant  also  con- 
tains two  sets  of  fibres,  the  longitudinal  ones  to  shorten  it, 
and  the  radiated  ones  serve  to  elongate  it,  and  it  is  not  to 
the  dilatation  of  the  first  that  this  last  effect  must  be  at- 
tributed. 

It  is  for  the  want  of  having  known  the  true  arrange- 
ment of  the  muscular  fibres  in  certain  parts,  and  not 
having  appreciated  the  different  effects  of  the  contraction 
of  these  fibres  according  to  the  direction  they  take,  that 
some  have  been  led  to  give  them  a force  of  expansion 
which  by  no  means  appears  to  be  inherent  in  them. 
What  takes  place  in  the  intestine  confirms  this  idea; 


MUSCULAR  SYSTEM  OF  ORGANIC  LIFE. 


203 


there  is  no  doubt  that  the  alternate  extension  and  contrac- 
tion which  agitate  this  viscus  depend  on  the  alternate  con- 
traction of  its  longitudinal  and  circular  fibres ; }?et  this 
fact  is  one  of  those  which  has  been  given  in  proof  of  the 
active  dilatation  of  the  muscles. 

F.  Meckel  has  presented  some  new  considerations  in 
support  of  the  latter,  drawm  from  the  different  states  in 
which  the  muscles  are  found  after  death,  from  the  mo- 
tions which  are  observed  in  the  iris,  from  the  variable 
dimensions  of  the  pupil  in  the  dead  body,  &c. ; but  if  we 
except  from  them  the  iris,  whose  motions  are,  I think, 
but  little  known,  and  whose  muscular  nature  is  moreover 
far  from  being  demonstrated,  the  contraction  alone  of  the 
muscles  perfectly  explains  almost  all  the  phenomena  of 
which  they  are  the  seat.  A single  one,  already  cited  by 
Bichat,  seems  at  first  favourable  to  the  active  elongation 
of  the  fibres,  inasmuch  as  it  appears  hitherto  inexplicable  ; 
it  is  the  force  with  which  the  heart  rises  up  and  tends  to 
dilate  itself,  even  when  the  blood  does  not  enter  its  inte- 
rior. But  is  this  fact,  though  obsciu’e,  more  conclusive, 
and  may  it  not  be  owing,  like  the  others,  to  some  partic- 
ular cause  which  is  unknown  to  us  ? Who  can  say  that 
the  diastole  and  systole  will  not  be  one  day  as  simple 
phenomena,  as  those  of  the  contraction  of  a voluntary 
muscle  ? 


204 


AUDITIONS  TO  THE 


MORBID  ANATOMY  OF  THE  MUSCULAR  SYSTEM. 

The  alterations  common  to  the  two  great  divisions  of 
this  system  may  be  united  in  one  description.  There 
are  a few  particular  ones,  which  will  be  noticed. 

I.  Alterations  in  the  External  Forms. 

Excess  of  nutrition  is  common  in  the  muscles ; but  it 
is  hardly  any  where  but  in  the  heart  and  the  bladder  that 
it  constitutes,  properly  speaking,  a disease ; it  is  charac- 
terized by  a remarkable  increase  of  size  and  often  of  den- 
sity. Atrophy  often  takes  place  in  the  external  muscles, 
from  the  want  of  exercise,  distension  or  some  other  cause. 
There  is  frequently  joined  with  it  a discolouration  of  the 
fleshy  fibres,  which  has  been  taken  for  a fatty  state,  as 
Bichat  has  already  observed.  The  pretended  fatty  alter- 
ation of  the  muscles  does  not  appear  to  me  to  exist,  at 
least  I know  of  no  instance  which  cannot  be  referred  to 
the  preceding  state,  in  which,  the  fleshy  fibres  disappear- 
ing in  part,  the  intermuscular  fat  predominates  and  is  con- 
founded in  its  colour  with  the  muscle  itself,  that  has  be- 
come yellowish.  But  we  find  by  analysis  fibrin  in  these 
muscles;  by  putting  some  of  it  on  brown  paper,  distinct 
fibres  are  discovered  after  the  animal  oil  has  been  absorb- 
ed, &c.  In  the  heart,  atrophy  occasions  the  dilatation  of 
this  organ,  its  passive  aneurism. 

The  muscles  lose  their  consistency  under  many  circum- 
stances ; the  heart  is  very  subject  to  this  alteration, 
which  has  been  described  by  M.  Laennec  in  his  excel- 
lent work  entitled  Traite  de  P Auscultation  Mediate, 
in  which  will  be  found  a great  number  of  interesting  facts 
upon  the  diseases  of  this  viscus.  The  softening  of  the 


MUSCULAR  SYSTEM  OF  ORGANIC  LIFE. 


205 


muscles  may  bring  on  their  rupture  ; that  of  the  heart 
has  been  often  observed  in  similar  cases,  especially  in  old 
people ; it  has  been  the  subject  of  a particular  work  of 
M.  Rostan.  . 

The  muscular  fibres  are  sometimes  elongated  from  the 
efiect  of  different  diseases  ; there  results  from  it  a more 
or  less  evident  weakness  of  their  action.  This  forced 
elongation  of  the  muscles  often  exists  at  the  same  time 
with  the  shortening  of  the  antagonists,  Avhich  is  then  the 
cause  of  it ; it  is  sufficient,  in  this  case,  to  counterbalance 
the  latter  in  order  to  restore  to  the  former  their  contractile 
faculty ; it  is  in  this  way  that  we  sometimes  succeed  in 
remedying  the  permanent  flexion  of  the  fingers,  by 
straightening  them  to  such  an  extent  that  the  extensors 
can  contract  again ; the  same  thing  applies  to  the  cure 
of  club-feet,  when  it  is  possible  to  bring  back  the  axis  of 
the  limb  to  its  primitive  direction. 

Shortening  has  not  the  same  inconveniences ; it  may 
extend  very  far  without  being  perceived  by  the  contrac- 
tility, as  proved  by  a preparation  in  Hunter’s  collection, 
in  which  the  humerus  had  experienced  a considerable  loss 
of  substance.  It  seems  on  the  contrary  that  this  short- 
ening power  was  increased  in  it ; at  least  it  is  then  in 
continual  exercise.  This  sort  of  retraction  is  very  fre- 
quent, and  is  most  often  connected  with  a weakness  of 
the  antagonists.  Contractions  from  the  scurvy,  certain 
morbid  curvatures  of  the  trunk,  club-feet,  that  we  have 
Just  noticed,  strabismus,  and  the  retraction  of  the  muscles 
of  the  leg  by  a continual  pain  in  this  part,  are  examples 
of  it.  The  little  finger  is  often  thus  retracted. 

Much  has  been  said  of  the  displacements  of  the  mus- 
cles, of  luxations,  and  hernias  of  these  organs.  What 
Poutean  has  written  upon  this  subject  may  be  advantage- 
ously examined. 


206 


AUDITIONS  TO  THE 


II.  Mierations  in  the  Organization. 

Inflammation  of  the  muscular  texture  is  still  doubtful. 
Purulent  centres  have  been  found  in  the  different  regions 
of  this  s^ystem,  but  they  may  have  their  seat  in  the  cellu- 
lar texture  interposed  between  its  fibres. 

A muscle  cut  transversely  retracts  powerfully,  as  has 
been  seen  elsewhere.  But  the  inferior  part  is  often  para- 
lyzed by  this  division,  because  a nerve  is  left  in  the  supe- 
rior, at  that  part  of  it  in  which  it  usually  penetrates  the 
muscle ; the  latter  preserves  on  the  contrary  its  irritability  ; 
the  retraction,  which  is  so  evident  in  amputation,  depends 
in  a great  measure  on  this  cause.  It  would  be  the  reverse, 
and  the  inferior  alone  would  contract  if  the  division  had 
been  made  higher  up.  In  all  cases,  to  these  phenomena 
succeed  those  of  reunion.  A new  fibrous  texture  fills 
the  space  between  the  two  ends,  which  it  unites  firmly 
together  ; if  it  be  short,  it  does  not  injure  the  contrac- 
tion, otherwise  the  muscle  would  gain,  as  has  been  said  ; 
if  the  intermediate  substance  be  long  and  extensible,  the 
motions  are  more  or  less  injured. 

Transformations  are  hardly  ever  seen  in  the  muscles. 
I have  however  found  in  them  fibrous  and  osseous  tu- 
mours, which  had  a knotty  appearance,  analogous  to  that 
of  the  tumours  of  this  kind  which  are  found  in  the  wminb. 
We  have  seen  above  what  should  be  thought  of  the  fatty 
transformation. 

Morbid  alterations  [dtgtnirations)  are  also  very  rare 
in  this  system.  Hydatids  may  sometimes  be  produced  in 
it ; they  are  common  in  hogs. 


MUSCULAR  SYSTEM  OF  ORGANIC  LIFE. 


207 


III.  ^Alterations  in  the  Development. 

The  muscles  of  animal  life  have  been  wholly  wanting- 
in  a foetus  ; there  was  under  the  skin,  only  a fatty  mass, 
formed  of  infiltrated  cellular  texture  more  or  less  consis 
tent ; at  other  times,  a part  of  these  muscles  is  wanting. 
The  heart,  in  very  rare  cases  it  is  true,  has  also  exhibited 
this  anomaly,  very  frequent  in  some  muscles  taken  sepa- 
rately. Nothing  is  more  variable,  besides,  than  the  ai-- 
rangement  of  the  muscular  system,  considered  in  relation 
to  its  external  forms.  We  often  find  supernumerary  mus- 
cles, or  those  which  should  exist  are  removed,  by  their 
conformation,  from  the  natural  order.  The  attachments, 
direction,  size  and  structure  exhibit  an  infinite  number  of 
varieties,  all  of  which  are  in  the  province  of  descriptive 
anatomy.  The  muscles  of  organic  life  are  not  exempt 
from  these  varieties  ; the  heart  alone  exhibits  a great 
number  of  them. 

Some  authors  have  spoken  of  muscular  transformations  ; 
but  the  examples  they  have  adduced  are  too  vague  to  be 
characterized.  There  seems  to  be  a preternatural  de- 
velopment of  the  muscular  texture  in  the  w’omb,  during 
pregnancy,  and  in  the  round  ligaments,  at  the  same 
period. 


ADDITIONS 


TO  THE 


MUCOUS  SYSTEM. 


Villi  of  the  Mucous  Membranes, 

Page  85. — “ The  delicacy  of  these  elongations  conceal^ 
their  structure,  even  from  our  microscopical  instruments, 
agents  from  which  anatomy  and  physiology  do  not  appear 
to  me  to  have  derived  much  assistance,  because  when  we 
see  obscurely,  each  sees  in  his  own  way  and  according  to 
his  own  wishes.” 

A great  number  of  observers,  both  ancient  and  modern, 
agree  in  many  points  in  relation  to  the  arrangement  of 
these  villi ; they  differ,  it  is  true,  upon  others,  but  it  is 
easy  to  see  that  oftentimes  the  foundation  of  their  obser- 
vation is  the  same,  and  that  the  whole  difference  consists 
in  the  manner  in  which  they  have  given  an  account  of 
37 


210 


ADDITIONS  TO  THE 


them.  The  intestinal  villi  have  been  the  particular  object 
of  their  researches.  The  following  is  what  is  the  least 
obscure  respecting  the  nature  of  these  elongations. 

The  villi  of  the  mucous  membranes,  examined  with  a 
microscope,  resemble  the  fibrous  parts  of  the  roots  of  cer- 
tain trees.  Yet  their  form  appears  to  be  rather  flat  than 
round,  and  the  name  of  leaflets  ffolioles)  which  has  been 
given  to  tbem  latterly  is  perhaps  better  in  this  respect 
than  that  of  villi.  Lieberkuhn  had  already  noticed  this 
arrangement  in  man,  but  he  admitted  that  those  of  ani- 
mals were  cylindrical,  and  consequently  filamentous  or 
villous.  They  terminate  in  a point,  which,  joined  to 
their  flattened  form,  has  led  some  to  compare  them,  from 
their  appearance,  to  the  leaves  of  the  grasses.  Rudolphi 
says  that  they  are  laminae,  small  scales  which  furnish  the 
whole  interior  of  the  intestine  ; this  is  not  very  far  from 
what  we  have  just  said. 

The  structure  of  these  elongations  is  the  point  that  has 
been  the  most  contested.  We  know  what  was  the  vesicle 
of  Lieberkuhn  ; this  anatomist  having  observed  that  the 
intestinal  villi  were  swollen  by  injection,  and  that  the  air 
driven  in  diffused  itself  in  them  and  gave  them  a spongy 
appearance,  thought  that  he  might  conclude  from  it  that 
they  were  in  a great  measure  formed  of  a kind  of  cellular 
vesicle,  in  which  the  vessels  terminated,  particularly  the 
lymphatics.  Hewson  has  made  observations  similar  to 
those  of  Lieberkuhn,  but  he  has  not  drawn  the  same  con- 
clusion from  them  ; according  to  him,  the  injection  makes 
the  villi  swell,  and  produces  in  them  a phenomenon  simi- 
lar to  that  of  erection  ; but  this  arises  from  their  being 
entirely  composed  of  a net-woi’k  of  vessels,  of  a sort  of 
plexus  similar  to  that  which  forms  the  erectile  textures. 
This  opinion  also  is  rejected  by  Rudolphi,  Mess.  Cuvier, 
Alb.  Meckel  and  many  other  modern  anatomists,  who  do 


MUCOUS  SYSTEM. 


211 


not  allow  that  these  elongations  contain  vessels,  at  least 
apparent  ones.  A viscid  matter,  a kind  of  jelly,  a sub- 
stance without  form  or  organization,  constitutes,  accord- 
ing to  these  authors,  the  villi,  which  have  exhibited  to 
them  with  a microscope  only  this  substance,  and  moreover 
opake  globules  situated  below  it.  This  matter  is  capable 
of  being  soaked  and  then  becomes  spongy  ; this  soaking 
can  take  place  from  within,  that  is  to  say,  on  the  side  of 
the  vessels,  as  well  as  from  without,  or  on  the  surface  of 
the  mucous  membrane.  The  lymphatic  vessels  may  arise 
from  this  substance,  which  Alb.  Meckel  compares  to  that 
which  constitutes  very  young  vegetables  at  the  period  of 
their  development.  This  description,  if  it  be  accurate, 
would  agree  very  well  with  the  facts  previously  observed, 
and  would  enable  us  to  explain  how  Lieberkuhn  saw  a 
vesicle,  how  Hewson  found  vessels,  &c.  There  is,  accord- 
ing to  Alb.  Meckel,  a circumstance  which  may  account 
for  the  various  forms  that  have  been  attributed  to  the 
villi  ; it  is  that  the  leaflets  they  represent  are  variously 
folded,  and  twisfed,  and  thus  assume  a variable  aspect, 
which  depends  on  their  situation  at  the  moment  they  are 
observed.  It  is  owing  to  this  that  Hedwig  calls  them 
cylindrical,  digit  if orm,  terminated  by  an  obtuse  summit ; 
that  others  have  compared  them  to  small  clubs,  &c. 

Many  anatomists  are  confident  that  there  are  apertures 
on  the  summit  of  the  villi,  and  that  they  are  the  orifices 
of  the  lymphatic  vessels.  They  are  not  however  agreed 
as  to  the  number  of  these  orifices.  Bleulanck-and  Hedwig 
allow  but  one  ; Cruikshank  and  Soemmering  have  seen 
from  six  to  ten.  Hewson  pretends  that  these  apertures 
do  not  become  distinct  until  the  villi  are  rendered  more 
prominent,  as  happens  from  injection  ; he  supposes  that 
it  is  the  same  during  life,  and  thus  explains  absorption  by 
the  erection  of  which  he  believes  these  elongations  sus- 


212 


ADDITIONS  TO  THE 


ceptible.  Those,  who  admit  the  opinion  that  was  last 
stated,  reject  all  kinds  of  openings  similar  to  ahsorhent 
orifices  •,  the  soft  matter,  ANdiich  has  been  noticed  above, 
is  in  the  place  of  them,  according  to  this  hypothesis. 

It  is  generally  thought  that  the  villi  receive  nerves  ; 
but  this  is  rather  from  a presumed  analogy  with  the 
papillae  and  on  account  of  the  sensibility  of  which  they 
are  the  seat,  than  the  result  of  inspection.  M.  Ribes 
has  injected  veins  in  them  from  the  vena  porta ; we 
have  seen  that  these  elongations  can  be  injected  from  the 
arteries  ; their  lymphatic  vessels  are  also  evident ; in 
order  to  see  them,  it  is  only  necessary  to  immerse  the 
membrane  in  alkohol ; the  fluids  which  they  contain  are 
coagulated  and  render  them  more  apparent. 

Mucous  Glands. 

Page  88. — ‘‘  I cannot  say  whether  nerves  penetrate 
them  ; analogy  indicates  it,  for  all  the  principal  glands 
receive  them.” 

These  small  sacs  are  now  distinguished  from  the  glands, 
and  described  under  the  name  of  follicles,  which  agrees 
much  better  with  their  nature.  They  appear  in  fact  to 
be  formed  by  a sort  of  inversion  of  the  membrane  in 
which  they  are  seated,  and  which  being  folded,  at  the 
place  where  they  are,  beneath  its  free  surface,  constitutes 
in  this  a real  cul-de-sac,  terminated  by  an  orifice  open 
upon  this  surface.  This  arrangement  is  very  evident  in 
the  sebaceous  follicles  on  the  skin,  with  which  the 
mucous  ones  have  so  great  an  analogy.  These  last  ex- 
hibit it  also  evidently  at  their  origin  ; there,  as  in  all 
the  points  where  their  epidermis  is  distinct,  we  can  raise 
this  up  entire  with  the  elongations  w’hich  it  forms  in  the 


MUCOUS  SYSTEM. 


213 


follicles.  This  is  rendered  still  more  evident  in  diseases, 
as  we  shall  see  in  the  article  upon  the  dermoid  system. 

Thus  the  mucous  follicles  must  have  a structure  analo- 
gous to  that  of  the  mucous  glands  of  which  they  form 
a part,  though  it  is  difficult  to  perceive  this  structure  ; 
they  have  no  excretory  duct  ; only  when  they  are  situat- 
ed below  the  chorion,  in  the  subjacent  cellular  texture, 
the  neck  of  them  being  more  or  less  elongated,  forms  a 
kind  of  tube.  The  orifice  by  which  they  terminate  is 
uniformly  more  narrow  than  their  bottom,  and  furnished 
with  villi  similar  to  those  of  the  neighbouring  parts.  Sir- 
Everard  Home  has  given  very  good  drawings  of  these 
different  objects. 

Most  of  these  small  bodies  are  insulated  and  irregularly 
disseminated,  in  greater  or  less  number,  in  the  whole 
extent  of  the  mucous  system.  I say  in  the  whole  extent, 
for  we  have  seen  where  they  are  but  little  apparent, 
analogy  induces  us  to  admit  their  existence  because  secre- 
tion is  constantly  going  on  there.  Besides,  their  size 
being  excessively  variable  in  the  parts  which  are  mani- 
festly provided  with  them,  it  is  natural  to  think  that  if 
they  are  not  seen  in  the  others,  it  is  simply  because  tbeir 
size  is  such  as  to  conceal  them  from  the  sight.  More- 
over, what  reasoning  indicates,  is  already  in  part  proved 
by  inspection  ; the  microscope  has  enabled  us  to  see 
follicles  in  many  membranes  in  which  they  could  not  be 
distinguished  by  the  naked  eye,  especially  in  the  pituitary 
membrane ; there  is  produced  on  the  skin  little  bunches, 
tumoui's  formed  by  the  development  of  the  follicles,  in 
places  where  they  had  not  been  before  met  with,  &c.  But 
in  some  parts,  the  follicles,  far  from  being  thus  insulated 
and  often  discoverable  with  difficulty,  are  agglomerated 
and  constitute  by  their  assemblage  masses  of  different 
forms,  and  the  arrangement  of  which  varies ; it  is  this 


214 


ADDITIONS  TO  THE 


which  has  led  to  the  distinction  of  the  follicles  into 
simple,  which  are  the  first,  and  into  compound,  among 
w'hich  are  ranked  the  caruncula  lachrymalis,  the  folli- 
cles of  Meibomius,  the  arytenoid  glands,  the  amygdalae, 
the  molar  and  buccal  glands,  the  glandulse  agminatm 
of  the  intestines,  the  prostrate,  &c.  Sometimes  each  of 
the  simple  follicles  which  compose  these  last,  has  its  own 
orifice  open  upon  the  mucous  surface,  as  is  seen  in  the 
caruncle.  Sometimes,  as  in  the  glands  of  Meibomius, 
they  open  into  each  other,  so  that  the  last  pours  out  the 
product  of  the  secretion  of  the  whole.  Sometimes  their 
openings  are  met  with  at  the  bottom  of  a sort  of  fold 
which  the  mucous  membi'ane  makes,  an  example  of 
which  is  furnished  by  the  amygdalae  ; the  mucous  lacunae 
belong  also  to  this  last  kind  ; they  may  be  considered,  as 
well  as  the  mucous  folds  of  the  amygdalae  and  the  foramen 
caecum  of  the  tongue,  as  great  follicles  which  receive 
smaller  ones  ; this  is  very  well  seen  in  the  urethra,  for 
example.  Finally,  the  molar  glands  and  the  prostate 
have  a real  I'amified  excretory  duct,  like  the  glands ; 
thus  these  organs  partake  of  the  glandular  nature,  and 
theirs  seem  as  it  were,  to  hold  the  middle  space  between 
this  and  that  of  the  follicles  properly  so  called. 

The  mucous  membrane  of  the  stomach,  that  of  the 
oesophagus  and  of  the  small  intestines  exhibit,  besides 
these  follicles,  small  superficial  cavities,  slight  depres- 
sions, which  Hewson,  who  first  observed  them,  compares 
to  the  cells  of  the  bees,  and  designates  this  arrangement 
by  the  name  of  the  alveolar  structure.  These  alveolae 
have  been  more  recently  described  by  Sir  Everard 
Home  ; they  can  only  be  seen  with  a microscope  ; in 
some  places,  however,  they  are  visible  to  the  naked  eye. 
They  do  not  appear  to  differ  from  the  follicles  but  in  this, 
that  their  aperture  is  broader  than  their  bottom,  the  fold 


MUCOUS  SrSTEM. 


21S 


of  the  mucous  membrane  being  of  small  extent,  which 
forms  them  ; they  are,  as  it  were,  the  rudiments  of  the 
follicles.  Their  number  is  few  at  the  bottom  of  the 
oesophagus,  where  they  begin  to  be  perceived,  between 
the  folds  of  this  canal  j it  increases  in  the  stomach  and 
especially  in  the  duodenum  ; in  this  intestine  and  in  the 
stomach,  the  depressions  have  nearly  the  same  breadth 
as  the  interstices  between  them  ; they  differ  in  this  from, 
the  alveolae  or  bees’  cells  which  are  in  fact  more  nume- 
rous, and  whose  interstices  are  much  smaller.  Their 
parietes  are  smooth  and  rounded  in  the  oesophagus  and 
in  the  neighbouring  portion  of  the  stomach  ; they  be- 
come unequal  as  we  examine  towards  the  intestines,  and 
are  furnished  with  small  leaflets  {folioles)  that  are  more 
and  more  evident. 

Sir  Everard  Home  has  examined  \vith  a microscope 
the  digestive  surfaces  of  different  animals.  It  follows 
from  his  observations,  that,  in  animals  who  are  nourished 
by  vegetable  substances,  the  follicles  of  these  surfaces 
have  a more  complicated  structure,  are  provided  with 
numerous  villi  at  their  orifices,  and  secrete  a more  active 
juice ; that  animals,  on  the  contrary,  whose  nourishment 
is  derived  from  the  animal  kingdom,  have  only  the 
alveolar  depressions  for  follicles  ; that  we  may  distinguish, 
in  this  respect,  three  species  of  follicles  which  exhibit 
three  different  degrees  of  complication  ; 1st,  those  which 
pour  out  a fluid  of  very  great  activity,  such  as  those  in 
the  ostrich ; 2d,  those  of  man  and  the  other  omnivorous 
animals  ; 3d,  those  of  which  we  find  the  type  in  the 
Java  swallow,  which  furnishes  a matter  that  possesses 
scarcely  any  solvent  power,  and  has  in  return  very  evi- 
dent nutritive  properties. 

The  secretion  which  takes  place  in  the  mucous  glands, 
united  to  that  of  the  sebaceous  glands,  constitutes  one  of 


216 


ADDITIONS  TO  THE 


the  three  principal  kinds  of  secretion  established  by  M, 
Chaussier  in  his  synoptical  tables,  viz.  the  follicular 
secretion.  It  differs  in  fact  in  many  characters  from 
the  perspiratory  secretion  or  exhalation  properly  called, 
as  well  as  from  the  glandular,  which  it  resembles  in 
others  ; 1st,  as  in  the  first,  the  secreted  fluid  appears  to 
be  brought  directly  by  the  extremities  of  the  arteries  ; 
2d,  this  fluid,  after  having  remained  a certain  time  in 
the  cavity  of  the  follicle,  and  having  no  doubt  been 
elaborated  there  anew,  is  thrown  out,  as  in  most  of  the 
glands,  by  the  peculiar  action  of  the  organ  which  has 
furnished  it. 

Development  of  the  Mucous  System. 

Page  125. — ‘‘  The  development  of  the  mucous  sys- 
tem follows  in  general  the  laws  of  that  of  the  organs 
to  which  it  belongs.  Early  in  the  gastric  apparatus, 
later  in  the  pulmonary  and  that  of  generation,  it  seems 
in  its  growth  rather  to  obey  the  impulse  it  receives,  than 
to  give  one  to  what  surrounds  it.” 

The  arrangement  of  the  mucous  system  is  very  differ- 
ent in  the  first  periods  of  conception,  from  what  it  will 
be  afterwards.  This  system  appears  to  be  continuous  at 
this  period,  as  well  as  the  cutaneous,  with  the  membranes 
of  the  ovum  ; such  at  least  seems  to  be  the  result  of  the 
observations  of  Wolff,  Oken,  Meckel  and  others. 

Wolff  has  traced  the  development  of  the  intestine  in 
the  chick.  He  has  seen  that  this  canal  is  at  first  very 
short,  straight,  open  before,  and  continuous  in  this  direc- 
tion, with  the  vitellary  membrane,  not  having  any  very 
precise  limit  to  indicate  the  place  where  one  terminates 
and  the  other  begins  ; that  afterwards  a contraction  de- 


MUCOUS  SYSTEM. 


217 


slgnates  this  place,  which  is  elongated  more  and  more, 
in  proportion  as  the  intestine  grows  at  the  expense  of 
the  yolk,  so  that  at  birth  these  two  parts  hold  together 
only  by  a narrow  pedicle,  which  disappears  completely 
when  the  yolk  has  been  entirely  absorbed.  Now,  the 
umbilical  vesicle  appears  to  perform  in  man,  in  the  first 
periods  of  the  intra-uterine  life,  the  same  uses  that  the 
yolk  or  the  vitellary  membrane  does  in  birds  ; many 
direct  facts  tend  even  to  prove,  that  it  is  in  the  same 
relation  as  this  last  to  the  intestine,  though  it  may  be 
very  difBcult  to  be  sure  of  it,  because  these  first  periods 
®re  passed  very  rapidly  in  the  mammalia,  and  the  foetus 
soon  acquires  another  mode  of  existence,  wholly  different 
from  that  of  birds.  However,  1st,  the  umbilical  vesicle 
is  so  much  the  larger  in  relation  to  the  foetus,  and  so 
much  nearer  the  umbilicus,  in  proportion  as  the  embryo 
is  younger ; 2d,  the  intestine  is  for  a long  time  in 
part  contained  in  the  base  of  the  umbilical  cord,  and 
afterwards  sends  sometimes  an  elongation  which  extends 
to  the  umbilicus  ; at  other  times  there  is  seen  a small 
duct  detached  from  the  umbilical  vesicle,  and  directed 
from  the  side  of  the  umbilicus,  for  a certain  distance, 
along  the  cord  ; 3d,  various  anatomists  have  seen  this 
vesicle  communicating  with  the  intestine  in  foetuses  of 
the  mammalia ; 4th,  Meckel  says  that  he  has  met  with 
a similar  communication,  in  man. 

From  all  these  considerations,  it  may  be  admitted, 
with  Oken,  Meckel,  &c.  that  what  is  evident  in  regard 
to  birds,  reptiles  and  fishes,  takes  place  also  in  man,  and 
that  the  alimentary  mucous  membrane,  by  being  con- 
founded with  the  umbilical  vesicle,  makes,  in  the  be- 
ginning, an  integrant  part  of  the  ovum.  The  same  may 
be  said  of  the  genito-urinary  membrane,  the  bladder 
having  intimate  connexions  with  the  allantois  ; the  skin, 
28 


218 


ADDITIONS  TO  THE 


on  its  part,  making  a continuation  with  the  amnios.  From 
this  it  results,  1st,  that  these  organs  are  among  the  earliest 
in  their  development,  if  they  be  not  even  formed  before 
all  the  other  parts  ; 2d,  that  the  embryo  is  in  nowise  dis- 
tinct from  the  ovum  in  the  first  periods  ; 3d,  that  its  two 
integuments,  viz.  the  external  formed  by  the  skin,  and 
the  internal  which  the  mucous  membrane  represents, 
instead  of  imitating,  as  in  the  adult,  a double  continu- 
ous sac,  folded  at  its  two  extremities,  are  as  it  were 
but  two  serai-canals  whose  circumference  is  wanting  in 
front. 

The  part  of  the  intestine,  which  corresponds  originally 
to  the  umbilical  vesicle,  and  which  serves  as  a point  of 
departure  for  the  development  of  the  rest  of  the  canal, 
remains  to  be  determined.  According  to  Oken,  it  is  the 
coscum  ; and  from  this  point  the  vesicle  sends  two  elon- 
gations which  form  the  stomachal  and  anal  intestines. 
Meckel  thinks  that  it  must  be  the  ileum,  because  it  is  so 
in  birds,  and  because  this  intestine  often  exhibits  appen- 
dices which  are  regarded  as  remains  of  the  vesicle,  and 
because  moreover  the  caecum  does  not  exist  in  all  the 
mammalia.  It  is  evident  that  these  are  but  conjectures. 

Besides,  if  it  be  true  that  the  mucous  system  com- 
mences by  having  the  arrangement  we  have  pointed  out, 
great  obscurity  still  hangs  over  the  manner  of  its  ulterior 
development,  and  the  way  in  which  this  semi-canal,  of 
a very  limited  length,  open  in  its  whole  extent,  is  com- 
pleted in  front  on  the  one  hand,  and  is  changed  on  the 
other  into  a long  tube,  no  longer  holding  to  the  vesicle 
but  by  a narrow  and  almost  impreceptible  canal.  It 
has  also  been  attempted  to  explain  in  another  way  the 
formation  of  this  system.  Some  have  said  that  the 
cavities  which  it  lines  are  hollowed  out  from  without 
inwards,  and  that  it  was  the  skin,  by  plunging  gradually 


MUCOUS  SYSTEM. 


219 


into  the  substance  of  the  embryo,  which  gave  rise  to 
the  mucous  membranes  ; it  is  on  this  account,  say  they, 
that  the  intestine  is  subject  to  interruptions  in  its  continu- 
ity, when  its  two  portions,  going,  one  from  the  mouth, 
and  the  other  from  the  anus,  are  not  perfectly  united. 
There  is  nothing  to  prove  this  assertion,  which  is  also 
contrary  to  many  facts.  Lucae  has  given  anofher  hy- 
pothesis, founded  upon  this,  that  the  cavity  of  the  intes- 
tine is  often  interrupted  in  many  places  ; this  proves, 
according  to  him,  that  this  canal  is  at  first  composed,  like 
the  vessels,  of  insulated  parts,  which  afterwards  go  to 
meet  each  other,  and  are  finally  confounded.  The  ap- 
pendices of  the  intestine  are  formed  when  these  parts, 
instead  of  joining  to  the  end,  are  united  together  by 
one  of  their  sides.  Tiedemann  and  Meckel  admit  this 
opinion  to  a certain  extent,  modifying  it  in  that  part 
which  makes  the  intestine  proceed  from  the  umbilical 
vesicle.  On  the  whole,  it  appears  that  new  researches 
are  required  on  this  point ; only  the  occlusions  of  the 
intestinal  tube  do  not  appear  to  me  by  any  means  to 
^lemonstrate  what  authors  have  advanced  ; these  occlu- 
sions do  not  take  place  till  after  the  complete  develop- 
ment of  the  intestine. 

There  are  neither  mucous  villi  nor  folds  in  the  first 
periods  of  conception.  Meckel  states  that  the  villi  com- 
mence by  longitudinal  folds,  which  are  afterwards  divid- 
ed into  small  insulated  prominences,  to  foi’m  them. 


220 


ADDITIONS  TO  THE 


MORBID  ANATOMY  OF  THE  MUCOUS  SYSTEM. 

I.  iterations  in  the  External  Forms. 

The  mucous  ducts  are  dilated  and  contracted  under 
many  circumstances  ; most  of  these  have  been  noticed 
in  the  article  on  the  Properties  of  Texture  of  this  system. 
These  changes  of  dimension  in  diseases  almost  always 
depend  on  an  obstacle  to  the  course  of  the  substances 
which  pass  through  these  ducts  in  a state  of  health  ; this 
is  evident  with  regard  to  the  excretories  ; the  least  exten- 
sible, such  as  the  urethra,  may  form,  in  this  case,  sacs  or 
dilatations  of  more  or  less  considerable  size,  before  break- 
ing ; the  bottom  of  the  mucous  lacunae  appears  to  be 
sometimes  the  particular  seat  of  these  dilatations.  Some- 
times the  obstacle  is  foreign  to  the  mucous  membrane, 
and  this  contracts  below  only  because  less  fluid  passes 
over  it,  and  keeps  it  separated ; sometimes  the  contrac- 
tion primarily  occupies  this  membrane,  whether  owing 
to  wounds,  ulcers,  inflammation  or  any  other  cause. 
In  either  case,  as  in  that  in  wdiich  the  fluids  take  another 
direction,  because  an  accidental  opening  gives  passage  to 
them,  the  portion  situated  below  is  not  obliterated,  as 
has  been  seen. 

The  mucous  membranes  are  however  capable  of  con- 
tracting adhesions  ; but  for  this  it  is  necessary  either 
that  the  secretion  of  mucus  should  be  suspended  there 
by  inflammation,  or  that  the  epidermis,  of  those  which 
have  one,  should  be  destroyed.  It  is  under  analogous 
circumstances  that  the  tongue  has  been  seen  to  adhere 
to  the  corresponding  parietes  of  the  mouth,  the  vagina 
to  disappear  by  the  mutual  adhesion  of  its  parietes,  the 


MUCOUS  SYSTEM. 


221 


Fallopian  and  Eustachian  tubes,  the  nasal  and  lachry- 
mal ducts,  &c.  to  be  obliterated.  These  adhesions  are 
however  much  less  common  here  than  in  the  serous 
system. 

The  mucous  membranes  are  the  seat  of  thickenings, 
growths  and  excrescences,  which  may  be  regarded  as 
enlargements  of  their  substance.  Polypi  are  an  altera- 
tion of  this  kind  ; they  are  divided,  as  is  well  known,  into 
many  species  ; many  belong  as  much  to  the  sub-mucous 
cellular  texture  as  to  the  mucous  membrane  itself,  which 
they  only  raise  up  ; there  are  some  which  arise  from  the 
periosteum  situated  in  certain  places  below  the  mucous 
membrane,  and  which  are  real  fibrous  bodies  ; some  are 
formed  by  a texture  which  differs  more  or  less  from  the 
natural  one,  and  come,  in  this  respect,  under  the  altera- 
tions of  texture ; such  are  those  that  are  called  cancerous. 

Various  organs,  that  are  covered  on  the  interior  by 
mucous  membranes,  are  exposed  to  defects  of  situation 
and  figure  in  which  these  membranes  participate  ; but  the 
latter  have  also  some  which  are  peculiar  to  themselves,  ex- 
amples of  which  are  furnished  in  the  various  displacements 
w'hich  the  mucous  membranes  of  the  rectum,  vagina,  blad- 
der, &c.  experience  in  the  prolapsuses,  inversions,  mucous 
hernias,  &c.  of  these  organs.  The  internal  or  villous  coat 
which  lines  these  viscera  on  the  interior  then  leaves  the 
other  coats,  and  is  extended  alone  to  a certain  extent, 
either  through  a natural  opening,  or  through  a preterna- 
tural one  arising  from  a separation  of  the  fibres  of  the 
nervous  coat.  The  preternatural  anuses  are  almost  always 
complicated  with  this  sort  of  displacement  to  which  the 
mucous  system  is  peculiarly  disposed  from  the  slight 
adhesion  of  its  subjacent  texture,  or  nervous  membrane 
of  the  ancients,  to  the  mucous  membrane  of  the  organs 
which  it  contributes  to  form. 


222 


ADDITIONS  TO  THE 


II.  Alterations  in  the  Organization. 

Inflammation  produces  in  tl\e  mucous  system,  besides 
the  alterations  of  colour  and  the  vascular  development 
which  are  peculiar  to  it,  suppurations,  false  membranes, 
ulcerations,  gangrene,  &c.  Of  all  these  phenomena,  no 
one  is  more  remarkable  than  the  formation  of  the  false 
membranes,  analogous  to  what  takes  place  in  the  serous 
membranes.  The  conjunctiva  in  ophthahnias  caused  b}" 
the  vapour  .of  the  hydro-chloric  acid,  the  rectum  in  irri- 
tating injections  administered  to  animals,  the  mucous 
membrane  of  the  mouth  and  the  pharynx  and  that  of  the 
air  tubes  in  croup  exhibit  this  alteration,  in  which  a soft 
layer,  like  the  skin  of  pork,  whitish,  and  slightly  adherent, 
covers  more  or  less  uniformly  the  inflamed  mucous  mem- 
brane. This  layer  has  hardly  ever  time  to  be  organized ; 
it  is  thrown  out  before,  or  the  inflammation  is  quickly 
fatal  ; Albers  has  found  it  vascular  in  croup  of  a chronic 
character. 

In  some  cases,  inflammation  seizes  more  particularly 
upon  the  mucous  follicles,  which  swell  and  then  become 
very  apparent;  this  variety  has  been  described  by  Roed- 
erer  and  Wagler.  Another  form  which  this  affection,  ex- 
hibits, though  less  evidently  than  on  the  skin,  is  that  of 
exanthema  ; it  is  observed  especially  in  those  parts  of  this 
system  that  are  in  the  neighbourhood  of  the  surface  of  the 
body. 

The  solutions  of  continuity  of  the  mucous  membranes 
cicatrize  like  those  of  the  skin ; this  is  what  is  seen  in 
some  ulcers  of  the  mouth  and  pharynx,  after  the  excision 
of  excrescences  from  the  genital  parts,  &c.  The  new 
texture  that  is  formed  is  whiter  and  more  resisting  than 


MUCOUS  SYSTEM. 


223 


the  first ; it  sometimes  forms  filaments  which  may  become 
troublesome. 

In  the  cases  cited,  (in  vol.  3d,  of  Bichat,)  the  mucous 
sj'stem  finally  experiences  the  cutaneous  transformation 
as  this  takes  place  whenever  it  is  in  contact  with  the  ex- 
ternal air  ; its  surface  is  then  dried,  the  mucous  fluids 
cease  to  lubricate  it,  the  villi  disappear,  an  appearance  of 
epidermis  takes  their  place,  and  the  membrane  becomes, 
in  some  measure,  more  stiff.  Various  parts  of  this  sys- 
tem can  also  be  changed  into  cartilages ; we  have  cited 
examples  of  this  when  treating  of  the  cai’tilaginous  system. 

Cancer  is  very  frequent  in  the  mucous  system  ; it  ap- 
pears under  many  forms  ; 1 st,  it  constitutes  excrescences 
similar  in  appearance  to  polypi,  but  very  different  in 
their  nature  ; the  rectum,  the  nasal  fossae  and  the  uterus 
are  subject  to  these  tumours.  2d.  Other  tumours  are 
subjacent  to  the  mucous  membrane,  which  finally  par- 
takes of  the  disease,  and  ulcerates  at  their  surface ; can- 
cers of  the  stomach,  the  oesophagus,  the  intestines  and 
the  bladder  most  often  assume  this  form.  3d.  Finally, 
cancerous  ulcers  have  their  primitive  seat  in  the  mucous 
system,  begin  on  its  superficies,  and  arrive,  not  for  a long 
time,  to  the  deep  parts  ; but  little  engorgement  accompa- 
nies them ; this  variety  is  common  on  the  lips,  the  glans 
penis,  and  especially  on  the  neck  of  the  uterus. 

III.  iterations  in  the  Development. 

Every  organic  system  may  be  considered  in  two  ways, 
as  may  be  seen  in  the  systems  previously  studied,  in  rela- 
tion to  the  altei’ations  that  may  take  place  in  its  develop- 
ments ; 1st,  this  development  is  sometimes  irregular  in 
the  places  where  it  should  take  place  naturally  ; hence 
the  defects  of  confoz’mation,  the  anatomical  varieties-  and 


224 


ADDITIONS  TO  THE 


the  anomalies  of  every  kind.  2d.  At  other  times,  it 
takes  place  preternaturally,  where  it  ought  not  to  take 
place  at  all,  it  invades  other  systems ; hence  organic 
ransformations  and  productions.  The  alterations  of  the 
first  kind  are  produced  by  causes  that  are  still  but  little 
known,  by  obstacles  which  have  arrested  the  natural  de- 
velopment at  one  of  its  periods,  and  have  thus  preserved 
forms  which  should  be  only  transitory,  by  diseases  that 
the  foetus  has  experienced  in  the  womb  of  the  mother, 
and  perhaps,  in  some  cases,  by  an  original  mal-formation 
of  the  germ,  &c.  Those  of  the  second  kind  take  place 
almost  always  in  diseases  ; sometimes  they  are  owing  to 
the  progress  of  age.  But  among  the  different  systems, 
there  are  some  which  appear  to  be  susceptible  of  one 
kind  of  alterations  only,  or  at  least  to  which  one  kind 
alone  is  common,  whilst  others  experience  both  equally, 
so  that  they  might  in  this  respect  be  classed  in  two  orders ; 
1st,  on  the  one  side  would  be  the  cellular  system,  which 
has  so  great  a tendency  to  be  produced  preternaturally 
and  so  little  to  have  defects  of  conformation,  and  the 
serous,  synovial  and  fibrous,  which  are  in  the  same  situa- 
tion ; with  regard  to  the  nervous,  the  muscular  and  the 
glandular,  the  reverse  is  true,  this  would  require  a subdi- 
vision ; 2d,  on  the  other  side,  the  osseous,  the  arterial, 
venous,  &c.  Now  the  mucous  system  belongs  rather  to 
this  last  order  than  to  the  first. 

Its  defects  of  conformation  are  numerous.  All  the 
mucous  canals,  without  excepting  the  intestines,  are  sub- 
ject to  deficiencies  to  a greater  or  less  extent,  and  some- 
times exhibit  in  their  course  interruptions  the  seat  of 
which  varies  ; sometimes  it  is  at  their  exterior  aperture 
that  they  are  found  imperforated  ; sometimes  it  is  farther 
in  that  their  cavity  is  obliterated,  either  owing  to  the 
parietes  being  confounded  together  or  closed  by  a sort  of 


MUCOUS  SYSTEM. 


225 


membrane,  or  because  the  canal  itself  has  entirely  disap- 
peared. These  canals  are  sometimes  deficient  in  a part 
of  their  circumference,  which  then  exhibits  preternatural 
openings,  fissures  and  communications  ; it  is  in  this  way 
that  the  vagina  is  seen  opening  into  the  rectum;  the  blad- 
der, destitute  of  its  anterior  parietes,  communicating  with 
the  hypogastric  region,  which  is  itself  destitute  of  parie- 
tes ; the  urethra  opening  into  the  perineum  ; the  palate 
establishing  a communication  between  the  mouth  and  the 
nasal  fossae,  the  velum  pendulum  separated  in  its  middle, 
the  lips  divided  as  in  hare-lip,  &c.  These  alterations  are 
often  only  the  remains  of  an  unfinished,  natural  develop- 
ment ; this  is  evident  in  the  hare-lip,  the  extroversion 
of  the  bladder,  &c. 

We  should  not  forget,  in  the  anomalies  of  development 
of  the  mucous  system,  the  digitiform  elongations  or 
digital  appendices  of  the  intestine.  These  elongations 
are  formed  by  all  its  membranes  ; we  have  seen  above 
the  attempt  that  has  been  made  to  explain  the  mechanism 
of  their  formation.  There  is  sometimes  found,  towards 
the  point  of  junction  of  the  pharynx  and  the  oesophagus, 
similar  appendices  which  retain  the  aliments,  which  occa- 
sions a sort  of  rumination  ; these  appear  to  be  consecu- 
tive and  formed  by  a hernia  of  the  mucous  membrane 
across  the  fibres  of  the  nervous  coat.  Calculi  of  the 
bladder  are  often  lodged  in  cavities  produced  by  the  same 
mechanism. 

We  may  consider  as  preternatural  mucous  membranes, 
1st,  the  membrane  which  lines  the  interior  of  abscesses  ; 
2d,  that  of  old  fistulous  canals. 

The  membrane  of  abscesses,  though  belonging  to  cavi- 
ties closed  on  all  sides,  has  in  fact  more  points  of  resem- 
blance to  the  mucous  than  to  the  serous  membranes  ; 
follicles,  it  is  true,  have  not  been  described  in  it ; but  its 
29 


226 


ADDITIONS  TO  THE  MUCOUS  SYSTEM. 


surface  is  soft,  pulpy  and  fungous,  like  that  of  the  mucous 
membranes;  when  put  in  water,  it  seems,  like  these  last, 
to  be  covered  with  filaments.  The  analogy  of  secretion 
is  an  additional  reason  in  favour  of  this  resemblance ; 
■what  is  more  analogous  to  mucus  than  pus  ? 

The  resemblance  is  still  more  evident  in  sinuses  and  fis- 
tulas terminating  on  the  exterior.  Hunter  had  already 
noticed  this  resemblance,  upon  Vv'hich  Bayle,  Laennec  and 
others  have  more  particularly  insisted.  The  membrane  of 
the  fistulous  canals  has  a distinct  epidermis  in  the  neigh- 
bourhood of  the  skin  ; farther  in,  it  disappears,  and  the 
membrane  becomes  red,  soft  and  fungous  ; it  would  be 
difficult,  in  this  place,  to  distinguish  it  from  a portion  of 
mucous  membrane  taken  from  the  sinuses,  for  example  ; it 
has  no  follicles,  but  its  fluid  is  almost  of  the  same  nature; 
below  it,  the  cellular  texture  is  often  hardened  and  more 
compact  than  in  the  natural  state,  as  is  seen  in  callosities  ; 
it  is  a result  of  inflammation  ; this  texture  is  sound  when 
the  inflammation  is  slight.  When  every  thing-  ceases  to 
pass  through  the  fistula,  it  contracts  and  its  canal  closes  ; 
it  differs  in  this  from  the  mucous  ducts,  which  are  not  ob- 
literated under  the  same  circumstances  ; but  its  oblitera- 
tion is  not  always  easy,  especially  in  the  neighbourhood 
of  the  skin,  and  in  general  fistulous  canals  have  but  little 
tendency  to  cicatrization  ; thus  we  endeavour  by  every 
method  to  develop  inflammation  in  them  or  to  destroy 
the  membrane  which  covers  them. 

In  abscesses,  as  in  fistulas,  the  preternatural  membrane 
derives  its  origin  from  the  cellular  texture,  and  is  owing 
probably  to  an  albuminous  exudation  of  the  nature  of  that 
which  constitutes  false  membranes. 


ADDITIONS 


TO  THE 


SEROUS  SYSTEM. 


MORBID  AXATOMT  OF  THE  SEROUS  SYSTEM. 

The  alterations  of  this  system  have  been  already  in 
part  pointed  out  by  Bichat ; the  following  is  what  we 
shall  add  to  what  he  has  said  of  them. 

I.  Alterations  in  the  External  Forms.  * 

Sometimes  the  serous  membranes  thicken  at  the  same 
time  that  they  are  increased  in  extent,  as  is  seen  espe- 
cially in  hernias  and  dropsies  ; this  increase  in  all  direc- 
tions supposes  a real  increase  of  nutrition  in  them  ; this 
cause  then  should  be  added  to  all  those  which  facilitate 
the  extension  of  these  membranes,  as  their  displacement, 


22S 


AUDITIONS  TO  THE 


the  disappearance  of  their  folds  and  their  peculiar  exten- 
sibility. (See  in  the  Serous  S^'stem  the  article  Exten- 
sibility.) In  other  cases,  the  thickness  of  these  mem- 
branes is  so  much  diminished  by  distension,  that  often- 
times they  are  found  with  difficulty.  This  is  not  rare 
in  umbilical  hernia. 

The  serous  system  is  subject  to  various  displacements, 
W'hich  alter  more  or  less  its  configuration.  These  dis- 
placements are  most  often  only  secondary,  and  are  owing 
to  changes  that  take  place  in  the  viscera  which  this 
system  covers,  or  in  the  parietes  of  the  cavities  which 
contain  these  viscera,  parietes  upon  which  it  is  also 
spread ; they  are  consequently  of  the  same  nature  as 
those  which  the  various  functions  produce  in  the  natural 
order.  Now  these  displacements  take  place  in  three 
ways ; 1st,  the  serous  membrane  leaves  the  parietes  and 
goes  upon  the  viscera  ; 2d,  it  leaves  these  last  to  go 
upon  the  first ; 3d,  it  extends  without  the  parietes,  forms 
a sac,  which  is  united  to  the  general  sac  that  it  forms 
within;  this  sac  is  constituted  by  the  portion  that  lines 
the  parietes;  but  in  time  the  membrane  is  also  detached 
from  the  viscera,  or  draws  them  out  when  it  adheres  to 
them  too  strongly.  The  sac  of  which  we  are  speaking 
is  produced  whenever  a viscus,  forced  through  the  pari- 
etes of  its  cavity,  carries  at  the  same  time  before  it  the 
serous  covering  of  these  parietes  ; this  is  the  sac  of  her- 
nias, the  hernial  sac  properl)^  so  called.  But  in  some 
cases,  this  sac  exists  previous  to  the  hernia,  and  the 
viscera  are  not  connected  wdth  it  till  afterwards  ; this  is 
what  takes  place  when  fat  accumulates  on  the  exterior  of 
the  peritoneum  for  example,  and  finally  forms  a mass,  the 
situation  and  weight  of  which  draw  it  outwards,  and 
which  also  draws  the  serous  membrane  with  it,  so  that 
this  forms  a sac  ready  to  receive  the  viscera  on  the  first 


SEROUS  SYSTEM. 


229 


occasion  ; an  arrangement  very  improperly  known  by 
the  name  of  fatty  hernia.  It  is  important  to  know  in 
practice  the  displacements  of  the  serous  membranes,  be- 
cause they  often  change  the  relation  of  the  parts  ; the  sac 
of  hernias,  in  particular,  presents  many  points  for  study. 

II.  Alterations  in  the  Organization. 

The  most  of  those  which  are  the  consequence  of 
inflammation  depend  on  changes  which  are  experienced 
by  the  fluids  that  are  naturally  exhaled  in  the  serous  cavi- 
ties, changes  which  vary  according  as  the  inflammation 
is  acute  or  chronic.  These  fluids  may  be  simply  in- 
creased in  quantity,  and  preserve  all  the  qualities  of  the 
serous  fluids,  or  they  may  be  altered  in  various  ways  ; 
from  this  simple  serum  to  opake  pus,  destitute  of  glo- 
bules like  that  of  the  cellular  texture,  there  is  an  infinity 
of  gradations.  Most  often  a matter  capable  of  concretion 
is  produced,  either  albuminous  flakes  swim  in  the  effused 
fluid,  or  a layer  of  the  same  nature,  a false  membrane., 
distinct  from  this  fluid,  covers  the  inflamed  serous  mem- 
brane, or  this  layer,  interposed  between  the  two  folds  of 
the  serous  membrane  not  separated  by  an  intermediate 
fluid,  establishes  between  them  an  adhesion,  soft  and  glu- 
tinous, similar  to  what  is  formed  between  the  lips  of  a 
wound  united  by  the  first  intention.  The  false  mem- 
branes begin  by  insulated  points  of  albuminous  matter, 
deposited  at  first  only  in  the  most  inflamed  places,  after- 
wards united  together,  and  then  forming  a continuous 
layer,  the  thickness  and  consistence  of  which  vary.  This 
layer  adheres  but  slightly  to  the  membrane  which  fur- 
nished it ; but  there  is  observed,  wdien  it  is  detached  from 
it,  that  a sort  of  indentations,  reciprocal  inequalities  unite 
one  to  the  other ; under  it,  the  serous  membrane  is  usually 


230 


ADDITIONS  TO  THE 


red  and  penetrated  with  vessels.  From  the  production 
of  these  false  membranes,  and  from  the  soft  and  skin-like 
adhesion  which  is  but  a slight  modification  of  them  since 
it  only  differs  from  them  by  the  absence  of  a fluid  suit- 
able to  maintain  the  separation  of  the  folds  of  the  serous 
membrane,  are  derived  all  secondary  effects  of  inflamma- 
tion, both  acute  and  chronic,  all  the  varieties  of  thicken- 
ing and  all  the  modes  of  adhesion.  The  albuminous  or 
skin-like  matter  of  the  false  membranes,  which  thickens, 
hardens,  is  organized  and  penetrated  with  vessels,  occa- 
sions these  varieties,  by  the  variable  forms  it  assumes  at 
the  moment  it  experiences  these  changes ; we  shall  not 
revert  to  the  manner  in  which  they  take  place ; the  de- 
velopment of  the  vessels,  which  is  the  main  point,  has 
been  examined  in  the  capillary  system.  We  may  now 
understand  how  miliary  granulations,  opake,  whitish, 
sometimes  extensive  and  supported  by  a narrow  pedicle, 
cover  the  serous  membranes  after  their  inflammation, 
the  evident  result  of  the  concretion  of  albumen  on  their 
surface  ; how  layers  of  the  same  nature  are  seen,  under 
the  same  circumstances,  upon  the  pericardium,  the  arach- 
noides,  the  tunica  vaginalis,  &c. ; how  these  different 
membranes,  the  pleura  and  peritoneum  in  particular,  often 
acquire  in  chronic  inflammation,  a thickness  double  or 
treble  that  which  they  before  exhibited  ; a thickness 
which  is  only  owing  to  the  presence  of  the  false  mem- 
branes organized  and  intimately  united  with  these  mem- 
branes, and  which  should  be  distinguished  from  that 
which  is  owing  to  a real  increase  of  nutrition  ; how  the 
cellular  and  filamentary  adhesions  arise,  those  in  which 
the  two  folds  of  tlie  membrane  are  entirely  confounded, 
and  the  filaments,  &c.  according  as  the  albuminous  matter 
is  stretched  a little  or  not  at  all,  or  as  on  the  contrary, 
this  matter  has  been  subjected  by  the  motions  of  the  part 


SEROUS  SYSTEM. 


231 


to  frequent  distensions,  according  as  the  inflammation 
has  continued  for  a longer  or  shorter  time  and  the  or- 
ganization has  been  more  or  less  perfect,  &c.  &c. 

A cicatrix  arises  from  the  serous  system  when  divided, 
though  it  was  doubted  for  a long  time.  It  is  linear  and 
afterwards  imperceptible  when  the  edges  of  the  wound 
have  remained  in  contact,  and  it  is  a cellular  membrane 
analogous  to  the  texture  whose  place  it  supplies  when  these 
edges  have  not  been  properly  brought  together ; we  may 
be  convinced  of  this  fact  by  examining  the  pleura  of  an 
animal  which  had  been  opened  some  time  before.  Thus, 
in  the  hernias  which  succeed  to  the  old  wounds  that  pene- 
trate the  abdomen,  the  peritoneum  forms,  as  usual,  a sac 
for  the  displaced  viscera,  though  the  contrary  has  been 
for  a long  time  maintained  ; only  this  sac  is  more  delicate 
and  seems  to  be  entirely  formed  by  the  cicatrix  which 
remains  more  extensible  than  the  neighbouring  texture. 

The  serous  membranes  are  ossified  ; no  one  is  exempt 
from  this  alteration,  which  appears  under  many  forms. 
They  are  usually  plates  appearing  rather  to  raise  up  the 
membrane  than  to  belong  to  it  ; sometimes,  however, 
these  plates  are  almost  naked  on  the  interior  of  this 
membrane.  The  tunica  vaginalis,  the  pleura  and  the 
peritoneum  contain  also,  in  some  cases,  a species  of  con- 
cretions similar  to  those  of  which  the  synovial  system  is 
the  seat,  and  to  which  we  shall  revert. 

M.  Laennec  has  described,  in  his  treatise  upon  tB.us- 
cultation  Mediate,  tumours  of  the  pleura  which  he 
refers  to  the  cerebriform  cancer  ; they  occupy  the  in- 
ternal face  of  this  membrane,  to  which  they  adhere 
strongly  ; their  environs  are  marked  by  a slight  redness 
owing  to  the  development  of  the  blood  vessels  ; they 
are  usually  in  small  number.  There  is  often  found,  in 
intestinal  ulcerations,  particularly  those  which  take  place 


232 


ADDITIONS  TO  THE 


in  phthisical  patients,  small  miliary  tubercles  which  make 
a part  of  the  serous  membrane  at  the  place  of  these  ulcer- 
ations. Various  authors  have  spoken  of  schirri  of  the 
serous  membranes  ; but  they  no  doubt  intended  to  desig- 
nate by  this  name  thickenings,  the  result  of  inflammation, 
and  not  a true  degeneration. 

III.  Alterations  in  the  Development, 

The  defects  of  conformation  are  quite  rare  in  the  sys- 
tem of  which  we  are  treating.  The  peritoneum,  the 
pleura  and  the  pericardium,  instead  of  representing  a sac 
without  an  opening,  are  sometimes  open  in  front,  and 
are  destitute  of  the  exterior  lamina  to  a certain  extent, 
so  that  their  viscera  are  bare.  The  arachnoides  has  a 
very  imperfect  organization  in  the  aencephalous  foetuses ; 
but  this  defect  is  but  a consequence  of  that  which  then 
exists  in  the  brain.  The  peritoneum  has  exhibited,  in 
some  rare  cases,  a sort  of  vesicle  or  secondary  sac  situ- 
ated in  its  interior,  communicating  with  it  by  a nar- 
row opening  and  containing  a part  of  the  abdominal 
viscera. 

Bichat  was  the  first  who  satisfactorily  proved  the  anal- 
ogy which  exists  between  the  cysts  that  are  preturnatu- 
rally  formed  in  various  parts  of  the  body  and  the  serous 
membranes.  (See  the  Cellular  System,  Vol.  1st,  and 
the  Serous  System,  Vol.  3d.)  He  has  refuted  the  opinion 
of  Louis  upon  the  mode  of  origin  of  these  cysts,  which 
he  regards  as  always  existing  prior  to  the  substances  they 
contain.  It  is  necessary  however  to  make  a distinction 
here  ; in  fact,  1st,  there  are  cysts  that  are  really  pre- 
existent, as  all  those  that  are  called  meliceris,  atheroma 
and  steatoma ; but  these  are  only  sebaceous  follicles 


SFROUS  SYSTE-M. 


exceedingly  dilated,  as  we  shall  see  in  another  place  ; 
(Vide  the  Dermoid  System  ;)  the  cysts  of  the  ovarium 
are  perhaps  also  in  the  same  situation,  as  they  appear  to 
be  owing  only  to  preexisting  vesicles  ; 2d,  there  are 
evidently  consecutive  ones,  which  are  formed  around 
various  bodies  coming  from  without,  around  the  blood 
in  apoplexy  and  pus  in  chronic  abscesses  ; 3d,  the  origin 
of  a great  number  is  obscure,  to  which  the  observations 
offered  by  Bichat  apply  perfectly. 

On  the  other  hand,  the  organization  of  cysts  is  far  from 
being  the  same,  though  in  general  they  belong  to  the 
serous  system.  Some  are  soft  and  almost  fluid,  as  it 
were ; it  seems  as  if  they  were  the  result  of  a simple 
exudation  ; some  of  this  species  have  been  found  in  the 
brain.  At  other  times  it  is  a membrane  but  little  differ- 
ent from  the  cellular  texture ; in  some  cases,  on  the  con- 
trary, it  is  a real  serous  cavity,  very  distinct  from  this 
texture,  as  is  seen  on  the  neck,  and  in  the  spermatic  cord. 
There  are  some,  the  structure  of  which  resembles  that 
of  the  mucous  membranes  ; others  have  a slight  resem- 
blance to  the  skin.  These  cj^sts  are  moreover  susceptible 
of  various  transformations  ; they  become  fibrous,  carti- 
laginous and  osseous  ; the  cancerous  and  other  degenera- 
tions are  also  met  with  in  them. 

The  substances  contained  in  these  preternatural  sacs 
ai’e  infinitely  various.  Solid,  foreign  bodies,  blood,  lim- 
pid serum,  viscid,  gelatinous  or  mucous  matter,  serous 
fluids  mixed  with  albumen  that  is  capable  of  concretion 
and  that  which  is  not,  fatty  fluid  matters,  or  those  with 
different  degrees  of  consistence,  a pultaceous,  stony  or 
cretaceous  substance,  and  concretions  more  or  less  hard 
may  be  contained  in  them.  Authors  have  been  much 
engaged  in  explaining  these  differences,  which  are  often 
observed  in  cysts  that  are  analogous  in  structure.  They 
30 


234 


ADDITIONS  TO  THE 


]iave  been  in  general  attributed  to  causes  purely  mechan- 
ical. It  is  thus  that  Bostock,  who  has  examined  the 
matter  of  many  cysts  found  in  the  interior  of  the  pelvis, 
after  having  praised  Cullen  for  rejecting  these  explana- 
tions, proposes  himself  one  of  this  kind,  by  which,  ac- 
cording to  the  state  of  the  heart  and  the  modifications 
Vv^hicli  result  from  it  in  its  action,  according  to  those 
which  the  animal  heat  experiences  or  the  disposition  of 
the  small  vessels,  there  would  pass  through  these  last, 
sometimes  the  serum  of  the  blood  almost  pure,  some- 
times this  serum,  with  a proportion  of  albumen,  either 
in  a fluid  or  concrete  state,  sometimes  these  two  matters 
united  to  fatty  matters  under  various  forms,-'and  all  the 
substances  in  fact  which  are  found  in  cysts.  It  is  evident 
that  the  mechanism  of  exhalations  is  too  little  known,  for 
these  explanations  to  be  accurate  ; the  causes  mentioned 
may  no  doubt  contribute  to  the  production  of  the  phe- 
nomenon, but  they  assuredly  do  not  alone  constitute  it. 

Hydatids  resemble  cysts  in  their  apparent  structure, 
though  they  are  very  diSerent  in  their  nature  ; this  is  so 
true  that  authors  are  not  often  agreed  upon  what  should  be 
called  cyst  and  what  hydatid.  The  following  however  are 
the  principal  characters  by  means  of  which  they  are  dis- 
tinguished ; 1st,  cysts  are  attached  to  the  surrounding  parts 
by  cellular  texture  and  blood  vessels  ; hydatids,  on  the 
contrary,  are  perfectly  free  ; it  is  true,  that  in  some  cases 
c}^sts  are  found  hardly  adherent ; but  these  cases  are  rare. 
2d.  The  parietes  of  the  cyst  have  always  more  or  less 
consistence ; the  hydatid  has  only  that  of  the  white  of 
an  egg  boiled.  3d.  The  hydatid  often  exhibits  in  some 
point  of  its  surface,  something  like  little  grains  which 
are  discoverable  by  the  naked  eye  or  with  a glass,  and 
which  seem  to  be  the  rudiments  of  other  hydatids  ; 
nothing  similar  is  seen  in  cysts.  Notwithstanding  these 


SEROUS  SYSTEM. 


235 


differences,  which  are  striking,  there  are  cases  where 
it  is  difficult  to  decide,  to  which  kind  of  productions  they 
belong ; this  is  almost  always  the  case,  for  example,  in 
the  vesicles  of  the  plexus  choroides,  and  still  more  in 
the  masses  of  the  same  kind  which  are  situated  in  the 
placenta,  and  the  nature  of  which  is  still  very-  doubt- 
ful. 


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if  • *. 

t ^rj(p'"^*'V/jLi  'f'  > 


■ ■ : *T 

■■■ 


ADDITIONS 


TO  THK 

SYNOVIAL  SYSTEM. 


Of  the  Synovial  Membranes. 

Page  179. — “ From  these  different  considerations  we 
may  be  easily  convinced,  I think,  that  notwithstanding 
the  adhesion  of  the  synovial  membrane  at  different  points, 
it  should  be  considered  ...  as  a real  sac  without  an 
opening,  everywhere  continuous  and  spread  upon  all  the 
organs  of  the  articulation.” 

The  reality  of  this  arrangement,  already  recognized  by 
Nesbith,  Bonn  and  Hunter,  and  which  some  persons 
have  doubted,  is  also  proved  by  the  following  considera- 
tions. 


238 


ADDITIONS  TO  THE 


1st.  Ill  inflammation  of  the  synovial  membrane,  the 
redness,  beginning  on  the  free  portion  of  this  membrane, 
extends  gradually  from  the  side  of  the  cartilage,  the 
surface  of  which  it  finally  reaches,  nearly  as  in  ophthal- 
mia, the  conjunctiva  reddens  gradually  upon  the  globe 
of  the  eye,  according  as  it  is  near  the  centre  of  the 
cornea.  This  gradation  is  easily  observed  in  dogs,  in  an 
articulation  that  is  opened,  and  the  interior  of  which  is 
left  in  contact  with  the  air.  The  redness,  in  this  ex- 
periment, never  reaches  the  substance  of  the  cartilage  ; 
it  is  confined  to  its  surface,  and  is,  as  it  were,  foreign 
to  it. 

2d.  There  is  a continuity  of  vessels  between  the  kind 
of  capsule  which  the  membrane  forms  around  the  osseous 
surfaces,  and  the  surface  of  the  cartilage,  as  is  evidently 
seen  in  the  preceding  experiment.  The  synovial  mem- 
brane of  the  knee,  injected  in  this  way,  exhibits,  in.  its 
adipose  ligament,  vessels  which  extend  directly  in  its 
portion  whicli  covers  its  cartilage,  to  the  two  extremities 
of  this  ligament. 

3d.  If  a bone  be  divided  perpendicularly  at  its  articu- 
lar extremity,  by  leaving  untouched  the  cartilage  of  this 
extremity,  and  if,  by  the  separation  of  the  two  halves  of 
the  bone,  the  cartilage  be  afterwards  ruptured,  the  two 
fragments  still  hold  together  by  the  synovial  membrane 
which  passes  from  one  to  the  other.  It  is  the  same 
when  the  surface  of  a cartilage  is  broken,  and  the  piece 
raised  up,  so  as  to  break  it  at  its  base  ; this  piece  still 
adheres  by  means  of  the  synovial  membrane,  w'hich  has 
not  been  ruptured. 

Let  us  conclude  from  these  different  facts,  that  the 
synovial  membranes,  far  from  being  limited  to  the  circum- 
ference of  the  articulations,  go  to  the  whole  extent  of  the 
osseous  surfaces,  upon  the  cartilages  which  cover  these 


SYNOVIAL  SYSTEM. 


239 


surfaces,  and  really  constitute  sacs  without  an  opening,  in 
every  respect  similar  to  those  of  the  serous  membranes, 
as  has  been  very  well  seen  by  Bichat. 

Synovial  Fringes. 

Page  181. — “ If  a remarkable  redness  sometimes 
distinguishes  these  bunches”  (the  pretended  glands  of 
Havers)  “ from  the  cellular  texture,  it  is  because  the  ves- 
sels are  more  concentrated  and  nearer  together  in  them. 
This  redness  of  some  pretended  synovial  glands,  the  only 
character  that  distinguishes  them,  is  then  as  it  were 
merely  accidental ; it  no  more  indicates  their  glandular 
nature,  than  it  proves  it  in  the  pia-mater,  in  which  it  is 
owing  to  the  same  cause.” 

What  is  here  said  of  the  fatty  bunches  so  improperly 
called  glands  of  Havers,  may  be  also  said  of  the  synovial 
fringes  which  surmount  these  bunches,  and  the  vascular 
structure  of  which  does  not  prove  that  they  are  excretory 
ducts.  These  fringes,  very  well  described  and  drawn  by 
Monro,  are  folds  of  the  synovial  membrane  floating  in 
the  articulation,  and  precisely  analogous,  in  this  respect, 
to  the  epiploons  of  the  serous  membranes,  and  the  epi- 
ploic appendices  of  the  intestines.  These  folds  are 
grooved  on  their  surface,  have  their  free  edge  cut  in 
various  ways,  as  can  be  very  well  seen  by  floating  them 
in  water,  and  resemble  in  some  measure  fringes  ; hence 
the  name  that  has  been  given  to  them,  and  which  may  be 
retained,  though  it  by  no  means  expresses  their  nature. 
Between  the  two  laminae  of  these  folds,  and  in  these 
laminae  themselves,  there  is  a great  number  of  vessels, 
arteries,  veins,  exhalants,  and  no  doubt  absorbents  also  ; 
thus  the  synovial  membrane  is  much  redder  there  than 


240 


ADDITIONS  TO  THE 


any  where  else.  It  is  to  the  presence  of  these  vessels,  the 
exhalants  in  particular,  that  the  following  phenomenon  is 
owing,  which  may  have  deceived  Havers ; if  these  folds 
are  pressed,  synovia  oozes  out  of  them,  which  evidently 
comes  from  the  open  exhalant  orifices,  and  not  from  par- 
ticular ducts. 

All  the  synovial  membranes  have  these  elongations, 
both  those  which  belong  to  the  tendons  and  those  destined 
to  the  articulations,  although  they  are  more  evident  in 
the  last  than  in  the  first ; among  these,  those  in  the  form 
of  vesicles  have  them  more  constantly  than  those  in  the 
form  of  sheaths.  The  great  articulations,  as  those  of  the 
knee  and  the  hip,  contain  the  largest  ; in  the  small  ones 
they  are  often  only  reddish  points  slightly  prominent. 
They  are  in  general  situated  near  the  place  where  the 
synovial  membrane  is  reflected  around  the  articular  carti- 
lage, and  usually  correspond  to  the  adipose  texture  of ' 
the  synovial  bunches,  in  part  contained  in  their  substance; 
those  of  the  tendinous  synovial  membranes  have  often 
between  their  laminas,  instead  of  this  texture,  soft  bodies 
like  gelatine,  the  fatty  bunches  analogous  to  the  articular 
ones  called  glands  of  Havers  being  wanting  in  many  of 
these  membranes. 

The  synovial  fringes,  from  the  great  number  of  vessels 
they  contain,  are  the  especial  seat  of  the  secretion  of 
synovia.  This  secretion  is  perspiratory,  and  evidently  of 
the  class  of  exhalations ; it  only  takes  place  there  more 
than  in  any  other  point  of  the  membrane,  because  the 
exhalants  are  more  numerous  there. 

The  following  is  the  idea  that  should  be  formed  of 
synovial  fringes  and  bunches;  1st,  blood  vessels  sur- 
rounded with  a more  or  less  abundant  adipose  and  cel- 
lular texture  ; 2d,  folds,  which  embrace  them  and  in 
which  they  particularly  terminate  ; folds  more  or  less- 


SYNOVIAL  SYSTEM. 


241 


numerous,  more  or  less  extensive,  and  whose  surface 
pours  out  synovia  in  abundance. 

The  mucous  system  exhibits  something  analogous  to 
the  fringes  of  the  synovial  membranes  in  the  folds  which 
exist  under  the  tongue,  and  upon  the  sides  of  the  frenum 
of  this  organ  ; these  folds  are  real  secretory  fringes,  de- 
signed to  increase  the  extent  of  the  exhalant  system. 

Parallel  hetioeen  the  Synovial  Membranes  and  the 
Serous  ones  properly  so  called. 

Page  ISl. — “ Though  the  synovial  membrane  is  very 
analogous  to  the  serous  surfaces,  it  must  however  exhibit 
differences  of  texture,  since  the  fluid  it  exhales  is  a little 
different.  Its  texture  has  not  the  suppleness  of  theirs. 
It  resists  maceration  longer.” 

The  synovial  membranes  might  justly  be  called  the 
serous  membranes  of  the  articulations  and  the  tendons  , 
yet  the  difference  of  the  parts  which  they  invest  gives 
them  peculiar  characters.  Most  of  these  characters  have 
been  stated ; the  following  are  some  more  of  them. 

The  synovial  membranes  receive  fewer  sanguineous 
and  other  vessels,  than  the  serous  membranes.  These 
appear,  as  it  were,  to  be  entirely  formed  of  vessels  in 
inflammation,  after  fine  injections,  &c.  ; the  synovial 
membranes  contain  much  fewer  under  like  circumstances. 
Compare  the  deep  tinge  of  the  serous  membranes  in 
asphyxia  with  the  much  less  evident  one  of  the  synovial 
membranes  in  the  same  case,  and  you  will  be  struck  with 
this  difference.  The  lymphatics  are  in  immense  quan- 
tity in  the  serous  membranes,  as  is  shown  by  injections  ; 
we  admit  them  from  analogy,  and  only  on  account  of 
their  functions,  in  the  synovial  membranes. 

31 


342 


ADDITIONS  TO  THE 


Maceration  discovers  in  these  distinct  laminae  and 
fibres  ; the  serous  membranes  have  them  also,  but  theirs 
are  much  less  apparent. 

The  synovial  membranes,  especially  those  of  the  artic- 
ulations, are  less  extensible,  and  seem  to  be  torn  sooner 
than  the  serous  ones ; at  least  ruptures  are  more  frequent 
in  them  than  in  the  latter.  This  difference  is  owing  per- 
haps solelj^j  or  in  great  measure,  to  this,  that  the  connex- 
ions of  the  membranes  are  not  the  same,  any  more  than 
the  causes  which  distend  them  ; the  one  fixed  to  the 
bones,  and  strongly  drawn  by  these  organs,  must  yield 
and  break,  as  happens  in  luxations,  the  others,  in  relation 
with  the  soft  parts  and  capable  of  yielding  themselves, 
are  merely  elongated,  as  is  seen  in  hernias. 

Existence,  Foi'ms,  Organization,  <§-c.  of  the  Synovial 
System  of  the  Tendons. 

Page  191. — ‘‘  There  are  many  synovial  membranes  the 
existence  of  which  is  variable ; such  as,  for  example,  that 
of  the  great  glutaeus,  in  the  place  of  which  thei’e  is  often 
found  only  a cellular  mass.” 

In  this  respect,  viz.  that  some  parts  of  this  system  are 
sometimes  wanting  and  are  then  replaced  by  cellular  tex- 
ture, the  synovial  system  of  the  tendons  is  confounded, 
more  perhaps  than  the  serous  and  the  articular  synovial, 
with  the  cellular.  But,  besides  the  latter  resembles  in 
many  places,  in  its  arrangement,  the  mucous  bursae  or 
synovial  membranes  of  the  tendons.  Wherever  great 
motions  take  place,  the  cellular  texture  is  loose,  lamel- 
lated  and  filled  with  fluids  ; its  laminae  are  separated  by 
broad  interstices,  imitating  more  or  less  exactly  the  cav- 
ity of  the  serous  or  sjuiovial  membranes,  so  that  it  may 


SYNOVIAL  SYSTEM. 


243 


truly  be  said,  that  these  membranes  exist  in  rudiment 
wherever  there  is  this  kind  of  motions.  This  is  what  is 
seen  on  the  thigh,  between  the  tendon  of  the  anterior 
rectus  and  that  of  the  triceps,  between  the  biceps  and  the 
anterior  brachialis  on  the  arm,  &c.  There  is  a sort  of 
gradation  according  to  the  mobility  of  the  parts,  in  this 
arrangement  of  the  cellular  texture ; the  integuments  of 
the  back  of  the  hand,  those  which  cover  the  anterior  face 
of  the  patella,  the  olecranon  and  acromion  have  under 
them,  on  account  of  their  frequent  sliding,  a cellular  tex- 
ture which  resembles  that  which  is  found  around  the  ten- 
dons, sometimes  even  true  mucous  bursas.  Finally,  where 
the  frictions  are  very  evident,  as  between  the  tendons 
and  the  bones,  these  are  nearly  constant.  They  are  found 
almost  uniformly,  with  a greater  or  less  degi’ee  of  devel- 
opment, between  the  skin  and  the  bones,  in  the  places 
where  these  parts  have  frequent  motions,  as  at  the  elbow 
and  the  knee,  so  that  in  those  places  there  are  generally 
sub-cutaneous  mucous  bursas,  as  there  are  tendinous  ones. 

There  is  a circumstance  which  may  also  have  an  in- 
fluence upon  the  existence  and  number  of  the  tendinous 
synovial  membranes  ; it  is  that  some  are  sometimes  in- 
sulated, and  sometimes  confounded,  as  is  seen  in  those 
which  line  the  sheaths  of  the  tendons,  according  as  these 
sheaths  are  themselves  separated  or  confounded  together. 

In  order  to  see  these  membranes  well  w’hen  they  exist, 
we  raise  the  tend^on  below  which  they  are  to  be  found, 
open  them  to  a small  extent,  and  force  into  this  opening 
air  or  the  matter  of  injection  ; they  are  distended  and  then 
become  very  apparent,  and  distinct  from  the  surrounding 
cellular  texture ; or  we  may  be  content  with  opening 
them  with  care  ; the  moisture  and  polish  of  their  surface 
serve  to  distinguish  them. 


244 


ADDITIONS  TO  THE 


The  tendinous  synovial  membranes  exhibit  some 
differences  in  their  forms,  besides  the  general  division 
into  vesicular  and  vaginal  pointed  out  above.  Their 
cavity,  instead  of  being  simple,  is  often  multilocular, 
(having  many  cells,)  divided  by  elongations  which  are 
detached  from  their  interior  ; these  elongations  are 
usually  soft,  but  in  some  cases  fibrous.  The  vaginal 
mucous  bursae  have  one  of  their  extremities  divided  in 
the  manner  of  digitations,  when  many  tendons,  united  at 
first  in  a single  sheath,  are  afterwards  separated,  &c. 

These  membranes  have,  as  we  have  said,  fringes  and 
sometimes  even  synovial  bunches  on  their  interior. 
Fourcroy  and  Ivoch  have  seen  villi  in  them.  The  vesi- 
cular synovial  membranes  are  of  a texture  more  dense 
and  compact  than  the  vaginal,  and  nearly  fibrous  in  some 
points. 

Their  fluid  is  yellowish,  sometimes  reddish  ; but  then 
this  tinge  is  accidental,  and  generally  a result  of  the 
transudation  which  takes  place  after  death.  It  appears  to 
be  thinner  in  the  synovial  membranes  of  small  extent, 
and  which  do  not  experience  considerable  frictions  ; 
thicker  and  more  viscid  in  the  others,  in  that  which 
covers  the  great  trochanter,  for  example,  and  whose 
motions  are  very  evident.  This  fluid  has  not  been 
analyzed  ; it  appears  to  be  formed  of  water,  albumen, 
soda  and  perhaps  some  salts  ; it  is  miscible  with  water 
in  any  proportion  ; heat  and  the  acids  coagulate  it  ; it 
turns  the  syrup  of  violets  green  ; when  dried,  it  is  trans- 
formed into  a kind  of  horny  lamina,  very  thin,  which 
burns  like  the  dried  Avhite  of  an  egg. 

The  mucous  bursse  are  very  extensible,  as  is  seen  when 
they  are  inflated  ; drops)'  also  furnishes  a proof  of  it. 
They  contract  when  the  distension  is  removed. 


SYNOVIAL  SYSTEM. 


24S 


MORBID  ANATOMY  OP  THE  SYNOVIAL  SYSTEM. 

I.  Alterations  in  the  External  Forms. 

The  distension  of  the  articular  synovial  membranes  by 
a collection  of  synovia  constitutes  hydarthrosis,  an  affec- 
tion that  is  not  common  and  which  is  observed  especially 
in  the  knee,  which,  in  general,  presents  the  most  frequent 
examples  of  all  the  diseases  of  the  articulations.  The 
quantity  of  the  accumulated  fluid  varies,  as  well  as  the 
nature  of  this  fluid  ; this  is  dependant  on  the  various 
complications  that  may  exist,  as  on  inflammation  in  par- 
ticular. The  distension  is  usually  more  evident  in  one 
or  several  points,  where  the  synovial  membrane  is  the 
least  supported  by  the  surrounding  parts. 

Dropsy  of  the  mucous  bursae  is  called  hygroma  when 
its  fluid  is  serous,  colourless  and  limpid,  and  ganglion 
when  it  is  a reddish,  thick  and  viscid  matter,  more  or 
less  similar  to  currant  jelly.  Neither  always  have  their 
seat  in  the  natural  mucous  bursae  ; they  are  sometimes 
preternatural  tumours,  a sort  of  cysts.  It  is  thus  that  the 
ganglions  are  formed  upon  the  back  of  the  hand  though 
there  are  no  mucous  bursae  in  this  place.  The  hygroma 
is  frequent  in  front  of  the  patella,  on  the  shoulder  and 
the  elbow,  places  where  the  cellular  texture  is  so  closely 
connected  with  the  synovial  membranes  ; it  takes  place 
especially  in  persons  who  have  these  parts  subjected  to 
constant  pressure. 

Anchylosis  exhibits,  as  is  known,  many  varieties.  In 
that  which  is  called and  which  should  be  considered 
a distinct  disease,  all  the  parts  which  enter  into  the  com- 
position of  the  articulation  are  thickened.  But  anchylosis 


246 


ADDITIONS  TO  THE 


properly  so  called,  affects  especially  the  synovial  mem- 
brane. Sometimes  filaments  of  various  extent  and  con- 
sistence traverse  the  articulation,  and  unite  the  two  oppo- 
site lamin:s  of  this  membrane  which  covers  the  articular 
surfaces  ; a sort  of  amphiarthrosis  then  exists ; an  articu- 
lation with  limited  motion  and  with  continuous  surfaces 
takes  the  place  of  the  one  which  existed  before  with 
great  motion  and  contiguous  surfaces  ; it  is  to  this  first 
variety  that  the  name  of  false  anchylosis  may  be  given, 
if  it  be  desirable  to  preserve  this  distinction.  Sometimes 
the  adhesion  between  the  two  surfaces  is  intimate,  the 
synovial  membrane  disappears  or  is  changed  into  cellular 
texture,  the  bones  are  united  together  and  are  finally 
deprived  of  the  lamina  of  compact  substance  which 
covered  their  extremity  ; this  is  true  anchylosis.  These 
two  kinds  of  adhesion  suppose  here,  as  in  the  preceding 
system,  an  anterior  inflammation. 


II.  Alterations  in  the  Organization. 

Besides  these  adhesions,  the  inflammation  of  the  syno- 
vial membranes  sometimes  produces  ulceration  in  them, 
though  it  is  quite  rare  ; Mr.  Brodie  has  related  two 
examples  of  it.  In  other  cases,  this  inflammation  termi- 
nates by  resolution,  and  there  results  from  it  only  a little 
stiffness  and  embarrassment  in  the  motions,  owing  to  the 
thickening  of  the  parts.  It  may  also  be  followed  by 
suppuration  and  effusions  of  various  kinds,  though  these 
effusions  are  observed  less  frequently  than  in  the  serous 
system. 

The  tendinous  synovial  membranes  exhibit  in  their 
inflammation,  fortunately  quite  rare,  the  two  modes  of 
adhesion  which  have  been  noticed,  viz.  filaments  and 


SYNOVIAL  SYSTEM. 


247 


adhesions  properly  so  called.  They  also  suppurate  at 
other  times,  and  then  their  tendons  most  usually  exfoliate. 

The  foreign  bodies  of  the  articulations,  which  some 
have  taken  for  concretions  formed  in  their  interior,  and 
which  others  consider  as  broken  and  detached  portions 
of  bone  or  cartilage,  are  always  situated  in  the  begin- 
ning, without  the  synovial  membrane.  They  are  osseous 
or  cartilaginous  productions  deposited  at  first  in  the  cellu- 
lar texture,  pushed  afterwards  by  degrees,  either  by  the 
various  motions  or  any  other  cause,  into  the  cavity  of 
this  membrane,  in  which  they  are  enveloped  and  which 
they  stretch  prodigiously  as  they  advance  ; it  terminates 
by  forming  for  them  only  a sort  of  pedicle,  which  at 
length  becomes  thin  and  finally  breaks  ; when  this  rup- 
ture takes  place,  the  body  is  loose  in  the  articular  cavity. 
The  state  which  it  then  exhibits  varies  ; its  consistence 
is  sometimes  very  soft  and  like  albumen,  at  others  carti- 
laginous or  osseous  ; in  some  cases  the  same  body  exhibits 
these  different  states.  The  long  continuance  of  these 
bodies  and  the  pressure  which  they  exert,  often  produce 
upon  the  articular  cartilage,  depressions  or  cavities  in 
which  they  are  lodged  ; these  depressions  have  led  to 
the  belief  that  there  was  a loss  of  substance  of  the  car- 
tilage, the  detached  fragment  of  which  produced  the 
foreign  body  ; but  we  cannot  conceive  of  any  cause 
capable  of  producing  such  a separation,  and  besides,  in- 
spection does  not  confirm  this  idea. 

Bodies  of  another  nature  are  developed  in  the  mucous 
bursae,  and  sometimes  also  in  the  articular  synovial  mem- 
branes. They  are  usually  extremely  numerous,  of  the 
size  of  a large  apple  seed,  flattened  in  various  directions 
and  of  a whitish  colour.  They  have  been  thought  to  be 
animated,  but  they  appear  to  be  inorganic  ; their  origin 
is  but  little  known.  Monro  has  also  found  in  the 


248 


ADDITIONS  TO  THE 


mucous  bursas  small  bodies  of  a peculiar  nature.  The 
same  author  says  that  he  has  met  with  cartilaginous  plates 
in  them. 

In  lohite  swellings,  an  improper  term  under  which  is 
confounded  various  degenerations  and  the  chronic  inflam- 
mation of  the  synovial  membrane,  this  often  becomes  the 
seat  of  a peculiar  degeneration  ; its  texture  becomes 
thickened,  greyish,  like  lard,  homogeneous  and  surround- 
ed with  soft  fungi,  the  presence  of  which  beneath  the  in- 
teguments may  lead  to  the  belief  that  there  is  an  abscess 
on  account  of  a kind  of  obscure  fluctuation  that  is 
thought  to  be  felt  there. 

III.  Mterations  in  the  Development. 

The  membranes  analogous  to  the  synovial  ones  that 
are  met  with  in  the  supplementary  articulations,  the 
consequence  of  luxations  not  reduced,  are  in  part  formed 
by  the  remains  of  the  old  one  that  is  ruptured  and  in 
part  by  the  real  production  of  a new  texture.  Fractures 
that  have  not  united  sometimes  have  a capsule  which 
seems  also  to  belong  to  the  synovial  system,  inasmuch 
as  it  contains  a serous  fluid,  as  we  have  said  elsewhere. 

The  synovial  cysts,  which  were  mentioned  at  the  be- 
ginning of  this  article,  are  preternatural  mucous  bursae. 

The  absence  of  some  tendinous  synovial  membranes, 
under  some  circumstances,  is  the  only  defect  of  confor- 
mation peculiar  to  this  system. 


ADDITIONS 


TO  THE 


GLANDULAR  SYSTEM. 


Intimate  Structure  of  the  Glands. 

Page  200. — “ The  glands,  like  all  the  other  organs,  . . . 
have  their  peculiar  texture  v^hich  especially  characterizes 
them,  which  belongs  only  to  them,  a texture  in  which 
the  arteries  communicate  with  the  veins  and  the  excreto- 
ries.  Let  us  not  push  our  researches  further ; if  we  do, 
we  shall  be  inevitably  entangled  in  conjectures.” 

Is  the  communication  direct  between  the  arteries  and 
the  excretory  ducts,  or  is  there  something  intermediate 
between  these  two  orders  of  vessels  ? The  results  obtain- 
ed by  Ruysh  and  Malpighi  in  the  solution  of  this  ques- 
tion, though  opposed  to  each  other,  are  however  equally 
32 


250 


ADDITIONS  TO  THE 


founded  upon  facts  rather  than  upon  mere  conjectures. 
Only  these  two  anatomists,  both  alike  commendable,  no 
doubt  directed  their  attention  to  glands  wholly  different. 
In  fact,  it  is  easy  to  see,  by  the  description  even  of  the 
glandular  system,  that  the  organs  which  are  comprised 
in  it,  even  by  restricting  as  much  as  possible  the  term 
glands,  and  by  applying  it  only  to  those  to  which  it  ex- 
clusively belongs,  by  taking  from  it  consequently  the 
mucous  and  sebaceous  follicles  or  glands,  of  which  we 
have  spoken  in  the  article  on  the  Mucous  System,  and 
the  glandiform  organs,  as  the  thymus,  the  thyroid,  the 
supra-renal  capsules,  &c.  ; it  is  easy  to  see,  I say,  that 
these  organs  vary  in  their  most  essential  properties,  and 
have  at  most  only  some  general  points  in  which  they 
approximate  each  other.  Thus,  as  it  regards  structure,  of 
which  we  are  now  to  treat,  the  opinion  of  Ruysh  seems 
to  be  perfectly  applicable  to  some  of  these  glands,  the 
liver,  the  testicles  and  the  kidneys  ; whilst,  in  respect  to 
others,  such  as  the  lobulated  or  conglomerated  glands  in 
general,  that  of  Malpighi  has  more  probability  in  its 
favour.  Inspection  and  experiment  may  be  resorted  to  ; 
the  one  shovvs  us,  in  the  first  of  these  glands,  an  evi- 
dent vascular  arrangement  in  all  the  points  of  the  organ, 
a continuity  that  can  be  traced  by  the  e)'e,  if  we  may  so 
say,  between  the  sanguineous  ramifications  and  those  of 
the  excretories ; in  the  second,  this  arrangement  is  much 
less  distinct  and  it  is  impossible  to  discover  the  continuity 
in  most  cases.  By  the  other  we  see,  in  injections,  the 
rapid,  easy  and  constant  passage,  in  the  excretory  vessels, 
of  the  matter  driven  in  through  the  arteries  in  one  class, 
the  liver,  kidneys,  &c.  ; this  same  passage,  slow,  difficult 
and  oftentimes  wanting  in  the  others,  as  in  the  salivary  and 
lachiyma!  glands,  pancreas,  &c.  It  may  then  be  possible 
that  the  little  grains  that  are  perceived  in  the  latter  may 


GLANDULAR  SYSTEM. 


251 


be  small  bodies  intermediate  between  the  arteries,  veins 
and  excretories,  as  Malpighi  thought,  species  of  follicles 
in  which  the  one  terminate  and  from  which  the  others  go 
off ; whilst  every  thing  may  be  vascular,  according  to  the 
hypothesis  of  Ru}'sh,  in  the  glands  of  the  other  kind. 
Hence  no  doubt  why  the  bloody  excretions  are  very 
much  more  frequent  in  the  latter,  especially  in  the  kid- 
ney, than  in  the  first. 


Influence  of  Nerves  iipon  the  Action  of  the  Glands. 

Page  223. — “ If  we  w'eigh  the  proofs  given  by  Bordeu 
of  the  influence  of  the  nerves  on  secretions,  we  shall  see, 
that  they  either  rest  upon  false  facts,  like  those  of  the 
section  of  the  nerve,  of  sleep,  &c.  or  upon  vague  data.” 

Every  thing  which  relates  to  the  peculiar  action  of  the 
glands  is  in  general  but  very  little  known,  as  is  the  case 
with  all  the  phenomena  which  take  place  in  the  interior 
of  the  organs.  All  that  is  known  upon  those  of  glandular 
secretion  is  confined  nearly  to  this  ; blood  containing  the 
materials  of  secretion  arrives  in  the  glands  by  the  arteries, 
except  in  the  liver,  which  receives  it  from  the  veins  and 
the  arteries ; this  blood,  in  traversing  the  glands,  under- 
goes changes  in  them  in  consequence  of  which  a fluid 
Avholly  different  from  it  is  produced.  But  do  these 
changes  take  place  suddenly,  or  slowly  and  as  the  blood 
advances  in  its  course,  and  what  is  their  nature  ? Are 
they  merely  the  result  of  the  configuration  of  the  parts 
and  a phenomenon  purely  mechanical  ? Is  it  a chemical 
or  galvanic  action  which  produces  them,  a doctrine  which 
seems  to  prevail  at  the  present  day  in  many  schools  ? Is 
it  a consequence  of  the  nervous  influence,  or  finally  do 


i52 


ADDITIONS  TO  THE 


all  these  causes  contribute  to  it  at  once  ? This  is  what  we 
are  ignorant  of. 

As  to  this  last  influence,  that  of  the  nerves  in  secre- 
tions, it  is  probable  that  it  exists,  as  Bichat  says,  though 
it  may  be  very  difficult  to  be  certain  of  it  directly.  The 
division  of  all  the  nerves  of  a gland,  suggested  b}'^  Bordeu, 
is  almost  everywhere  impracticable.  The  experiments 
related  by  Bichat  will  no  doubt  be  found  far  from  being 
conclusive  The  following,  which  are  perhaps  scarcely 
any  more  so,  but  in  which  however  the  results  seem  to 
he  a little  more  decisive,  and  which  besides  appear  to  be 
so  much  the  more  remarkable,  as  they  are  in  evident 
contradiction  to  the  first,  are  made  by  Mr.  Brodie. 

1st.  The  brain  having  been  removed,  respiration  being 
supported  artificially,  that  the  circulation  might  not  stop 
and  that  the  animal  might  continue  to  live,  the  urine  was 
no  longer  secreted.  This  fact  does  not  prove  positively, 
it  is  true,  that  the  cerebral  action  has  an  influence  upon 
the  function  which  the  kidney  has  of  secreting  urine  ; for 
it  might  be  that  the  circulation  was  weakened  in  this  case 
so  as  to  render  the  secretion  less  active ; it  is  however  a 
strong  presumptive  evidence  of  this  influence. 

2d.  In  order  to  be  able  to  appreciate  the  mode  of  influ- 
ence of  the  nerves  of  the  eighth  pair  upon  the  mucous 
secretion  of  the  internal  coat  of  the  stomach,  a secretion 
not  sufficiently  abundant  in  the  natural  state  to  enable  us 
to  obtain  striking  results,  it  has  been  attempted  to  increase 
the  products  of  it  by  giving  to  an  animal  arsenic  and 
other  poisonous  substances  of  the  class  of  corrosive 
poisons,  which  produce,  among  other  phenomena,  an  ac- 
cumulation of  the  mucous  and  other  fluids  that  are  con- 
stantly poured  out  on  the  internal  coat  of  the  stomach ; 
the  nerves  of  the  eighth  pair  have  afterwards  been  divid- 
ed. At  the  death  of  the  animal,  that  mass  of  fluids  is 


GLANDULAR  SYSTEM. 


253 


not  found,  which  is  never  wanting  under  any  other  cir- 
cumstance. It  seems  to  follow  from  this  that  the  integ- 
rity of  these  nerves  is  necessary  to  enable  the  mucous 
dands  or  follicles  of  the  stomach  to  answer  to  the  stimuli 
which  are  directly  applied  to  them. 


MOKBID  ANATOMY  OP  THE  GLANDULAR  SYSTEM. 

The  extreme  diversity  that  exists  in  this  system  makes 
it  almost  impossible  to  describe  in  a general  manner  the 
morbid  alterations  of  the  glands  ; there  are  too  many 
peculiarities  belonging  to  the  descriptive  anatomy,  and 
too  few  common  points  ; it  would  require  almost  as 
many  divisions  as  there  are  organs  comprehended  under 
the  name  of  glands ; it  is  the  same  with  regard  to  the 
description  of  this  texture  considered  in  the  natural  state  : 
what  we  shall  now  say  will  be  a proof  of  it. 

I.  iterations  in  the  External  Forms. 

Increase  of  size  as  well  as  the  circumstances  under 
which  it  takes  place,  have  been  noticed  {Bichat,  vol. 
3d,)  in  the  glands  that  are  in  pairs  ; the  glands  that  are 
not  in  pairs,  like  the  liver,  rarely  experience  it,  without 
it  is  joined  with  an  alteration  of  texture. 

Atrophy  comes  on  in  two  ways,  viz.  1st,  from  com- 
pression, as  from  an  external  pressure  long  continued,  or 
when  a tumour  has  gradually  destroyed  the  interior  of 
an  organ  ; 2d,  from  want  of  exercise,  as  takes  place  in 
certain  glands  from  the  progress  of  age. 


254 


ADDITIONS  TO  THE 


We  know  all  the  varieties  of  consistence,  and  all  the 
differences  of  colour  which  the  liver  exhibits  in  diseases. 
The  testicle  and  the  kidney  also  present  some  of  them ; 
the  other  glands  are  much  less  subject  to  this  kind  of 
alteration. 

Displacements  are  observed  in  those  of  these  organs 
situated  in  the  abdominal  cavity,  some  of  them,  as  the 
spleen,  can  be  drawn  from  their  place  in  hernias. 

II.  Jllterations  in  the  Organization. 

Inflammation  of  the  glands  affects  those  rather  with  a 
dense  and  compact  texture,  than  the  granulated  ones  ; yet 
the  breast  is  particularly  disposed  to  it.  Besides,  it  is 
necessary  to  distinguish  this  inflammation  from  that  of 
the  cellular  texture  and  the  neighbouring  lymphatic 
glands,  this  is  important  especially  with  regard  to  the 
parotid,  which  is  often  thought  to  be  inflamed,  whilst  its 
texture  is  sound  and  the  cellular  texture  which  surrounds 
it  is  alone  affected.  This  inflammation  rarely  terminates 
in  gangrene ; on  the  contrary,  suppuration  and  induration 
are  the  frequent  consequences  of  it. 

Some  glands,  placed  on  the  exterior,  when  compre- 
hended in  wounds,  become  the  base  of  a cellular  cicatrix ; 
but  the  glandular  texture  is  not  reproduced. 

The  extreme  frequency  of  transformations  of  every 
kind,  in  the  system  of  which  we  are  treating,  has  already 
arrested  the  attention  of  Bichat.  (Vol.  3d.)  Yet  it  is  still 
necessary  to  establish  a distinction  in  this  respect ; in 
fact,  1st,  most  of  these  transformations  have  been  observ- 
ed in  the  liver,  the  kidney,  the  testicle  and  the  mamma, 
whether  they  are  formed  of  textures  analogous  to  those 
which  exist  in  a natural  state,  or  whether  textures  wholly 
foreign  to  the  economy,  except  in  a state  of  disease,  con- 


GLANDULAR  SYSTEM. 


255 


stitute  them  ; 2d,  who  does  not  know,  on  the  contrary, 
how  rare  they  are  in  the  lachrymal  and  salivary  glands, 
and  even,  to  a certain  extent,  in  the  pancreas  ? 

III.  Alterations  in  the  Development. 

Notwithstanding  the  numerous  irregularities  in  the 
forms  of  the  glands,  we  must  not  however  take  literally 
what  has  been  said  (Vol.  3d.)  of  the  frequency  of  these 
irregularities,  compared  with  their  rareness  in  the  organs 
of  animal  life.  The  difference  is  by  no  means  so  striking 
as  Bichat  has  pretended  ; we  have  seen  elsewhere  that 
the  brain  has  not  always  precisely  the  same  conformation 
in  its  two  hemispheres,  and  that  Bichat  was  himself  a 
proof  of  it  ; his  cranium  exhibited  in  fact  this  singularity, 
that  the  forehead  was  much  more  prominent  on  the  right 
than  on  the  left,  and  that  an  opposite  arrangement  exist- 
ed at  the  occiput,  whence  there  resulted  an  inequality  of 
size,  at  the  right  and  the  left,  in  the  anterior  and  pos- 
terior lobes  of  the  brain.  The  bones,  muscles  and  nerves 
exhibit  analogous  varieties.  On  the  other  hand,  the 
glands  are  by  no  means  so  variable  that  this  would  fur- 
nish a character  sufficient  to  distinguish  them  from  the 
preceding  organs.  Their  varieties  are  often  insignificant ; 
as  in  a bone,  a groove,  a vascular  foramen  or  a depression 
for  a tendon  have  not  always  precisely  the  same  position, 
extent  and  direction ; so  in  a muscle,  the  length  of  the 
fleshy  fibres,  the  extent  of  the  tendon,  the  situation  and 
number  of  the  intersections,  &c.  vary  ad  infinitum,  and  it 
is  of  but  little  consequence  in  a gland,  whether  a lobe  be 
a little  larger,  an  edge  more  or  less  hollowed  out,  an  ex- 
tremity more  or  less  extended,  &c. 

Besides,  the  glandular  forms  are  more  or  less  constant 
according  to  the  organs  in  which  they  are  examined. 


256  ADDITIONS  TO  THE  GLANDULAR  SYSTEM. 


The  kidney  alone  exhibits  almost  as  many  varieties  as  all 
the  other  glands  together  ; sometimes  by  itself  or  united 
to  that  of  the  opposite  side,  sometimes  divided  as  in 
the  foetus  into  many  lobes,  sometimes  situated  in  the  pel- 
vis or  in  front  of  the  vertebral  column,  there  are  but  few 
subjects  in  winch  it  is  perfectly  similar.  The  liver,  the 
salivary  and  lachrymal  glands,  &c.  exhibit  less  of  these 
differences. 

The  glandular  texture  is  never  preternaturally  pro- 
duced. 


ADDITIONS 


TO  THE 


DERMOID  SYSTEM 


Colouring  Matter. — Mucous  Body. — Papillae. 

Page  273. — “ It  is  necessary  to  distinguish  two  por- 
tions in  the  capillary  system  exterior  to  the  chorion. 
1st.  One  is  constantly  filled  with  the  colouring  substance 
of  the  skin.  2d.  The  second  is  constantly  pervaded  by 
many  fluids.  These  two  portions  are  entirely  indepen- 
dent, and  have  probably  no  kind  of  communication.” 

The  colouring  matter  of  the  skin  forms,  in  the  negro,  a 
layer  distinct,  not  only  from  the  chorion  and  the  epidermis, 
in  which  Riolan  thought  it  placed,  but  also  from  the  other 
parts  of  the  mucous  body,  with  which  Malpighi  con- 
founded it.  This  matter  exists  also,  though  less  apparent, 
in  the  whites  who,  without  it,  would  not  differ  from 
33 


258 


ADDITIONS  TO  THE 


albinos,  who  are  entirely  destitute  of  it.  The  mucous 
body,  which  Malpighi  regarded  as  a mere  coat,  a sort 
of  varnish  covering  the  papillae,  a varnish  for  which  Bi- 
chat has  substituted  a reticular  body,  essentially  formed 
of  vessels,  and  divided  into  two  portions  independent  of 
each  other,  appears  in  fact  to  contain  many  distinct  parts 
observed  in  the  skin  of  the  negro  by  M.  Gaultier,  and  in 
that  of  quadrupeds  by  M.  Dutrochet. 

If  the  skin  of  the  heel  of  a negro  be  cut,  a little 
obliquely  as  to  the  substance  and  transversely  to  the 
direction  of  the  lines  which  the  papillae  represent,  there  is 
distinguished  upon  the  divided  edge  the  following  objects; 
1st,  immediately  above  the  papillae,  and  making  a part  of 
them,  there  is  found  a series  of  small  vascular  fasciculi, 
designated  by  M.  Gaultier  by  the  name  of  sanguineous 
hunches.  2d.  Between  these  bunches  and  the  epider- 
mis, is  seen  a black  undulating  line,  placed  between  two 
white  lines,  one  of  w^hich  separates  it  from  the  first  layer, 
and  forms  the  deep-seated,  whitish  layer,  composed, 
according  to  M.  Gaultier,  of  white  vessels.  3d.  The 
black  line  which  is  above,  or  the  coloured  layer,  takes 
the  name  of  gemmule,  on  account  of  its  undulations, 
which  make  it  appear  as  if  composed  of  an  infinity  of 
small  concave  bodies  embracing  the  summit  of  the  papil- 
lae ; each  of  these  small  bodies  receives  two  sanguineous 
bunches,  the  summit  of  the  papillae  being  bifurcated,  as 
we  shall  say  hereafter.  4th.  Finally,  immediately  below 
the  epidermis  is  the  second  colourless  layer,  or  the  super- 
ficial whitish  layer,  formed  of  serous  vessels  like  the 
first. 

There  are  then,  according  to  this,  four  parts  in  the 
mucous  body,  and  by  adding  the  two  white  layers  to  the 
two  portions  admitted  by  Bichat,  and  which  might  then 
be  regarded  as  real  insulated  layers,  we  should  have  the 


DERMOID  SYPTEM, 


259 


true  structure  of  this  body.  But  among  these  layers, 
the  first,  formed  by  the  sanguineous  bunches,  does  not 
really  belong  to  the  mucous  body  ; it  is  nothing  else  than 
the  termination  of  the  vessels  ramified  in  the  papillae, 
and  forms  a part  of  what  was  formerly  called  the  papil- 
lary body ; so  that  the  number  of  layers  which  consti- 
tute the  mucous  body  may  be  reduced  to  three ; this  is 
what  M.  Dutrochet  has  done  in  the  analysis  he  has  given 
of  the  structure  of  the  skin  of  quadrupeds.  He  has  re- 
cognized the  existence  of  these  layers,  such  as  M.  Gaul- 
tier has  described  them  ; only  he  has  designated  them  in 
the  following  manner  ; the  skin  is  composed  according  to 
him,  1st,  of  the  dermis;  2d,  of  the  papillae;  3d,  of  the 
epidermoid  membrane  of  the  papillae,  which  is  the  deep- 
seated  whitish  layer  of  M.  Gaultier ; 4th,  of  a coloured 
layer;  5th,  of  a horny  layer,  which  answers  to  the  super- 
ficial lohitish  layer;  6 th,  of  epidermis. 

The  existence  of  a mucous  body  between  the  dermis 
and  epidermis,  composed  of  at  least  three  layers  super- 
added  to  each  other,  seems  to  be  demonstrated  by  the 
results  which  we  have  just  stated  ; yet  all  anatomists  do 
not  admit  this  existence.  According  to  M.  Chaussier, 
the  skin  has  but  two  distinct  parts,  the  dermis  and  the 
epidermis  ; the  one  containing  all  the  organic  elements 
of  this  membrane,  without  the  possibility  of  establishing 
the  boundary  between  these  elements,  the  other  being  the 
inorganic  or  non-vital  portion  of  it.  Haller,  Camper, 
Blumenbach,  &c.  were  inclined  to  reject  the  mucous  body 
in  the  skin  of  the  white,  and  to  admit  its  existence  only 
in  that  of  the  negro. 

When  the  epidermis  is  removed  by  maceration  from  a 
portion  of  very  black  skin,  from  that  of  the  scrotum  of 
the  negro,  for  example,  the  colouring  matter  remains  in 
part  upon  the  dermis  and  in  part  upon  the  epidermis, 


260 


ADDITIONS  TO  THE 


more  however  upon  the  latter ; but  if  the  maceration  be 
continued,  this  matter  is  detached  from  both,  and  depo- 
sited at  the  bottom  of  the  vessel,  where  it  can  be  collected  ; 
it  has  great  analogy  with  the  colouring  matter  of  the 
blood.  This  matter  does  not  appear  to  be  formed  in  the 
coloured  layer  or  gemmules  in  which  it  has  its  seat; 
the  papillae  are  the  secretory  organs  of  it,  as  well  as  of 
this  layer  itself.  When  we  produce  by  a blister  the  sepa- 
ration of  the  epidermis  and  of  the  three  subjacent  layers 
from  the  mucous  body,  the  denuded  dermis,  at  first  red 
and  deprived  of  its  colouring  matter,  afterwards  takes  it 
again  ; when  the  blister  is  dry  this  matter  is  reproduced 
in  the  form  of  little  black  points  which  gradually  enlarge 
and  are  finally  confounded  together,  so  that  the  cicatrix 
is  black  though  the  mucous  body  may  have  been  removed. 
M.  Gaultier  attributes  principally  to  tbe  hairs  the  func- 
tion of  secreting  this  matter,  because  it  is  more  abundant 
where  the  hairs  exist,  and  on  account  of  the  form  it  as- 
sumes in  the  case  of  which  we  have  just  spoken  ; but 
since  it  is  met  with  in  all  parts  of  the  skin,  it  is  not 
probable  that  its  source  is  different  according  to  the  place 
it  occupies. 

Besides,  the  colouring  matter  of  the  skin  is  by  no 
means  stagnant  in  the  mucous  body  ; the  modifications, 
which  it  experiences  under  many  circumstances,  show 
that  it  is  incessantly  brought  there  and  again  taken  up  by 
vessels,  and  consequently  subjected  to  a real  circulation. 
Thus  various  authors  cite  examples  of  changes,  almost 
instantaneous,  taking  place  in  the  colour  of  the  skin,  of 
women  becoming  black  during  pregnancy,  of  men  who 
havm  experienced  the  same  change  from  age  or  extreme 
grief;  thus  negroes  whiten  more  or  less  in  diseases,  old 
age,  &c.  At  birth,  the  negro  is  not  coloured  ; his  skin, 
similar  to  that  of  the  white,  is  red  like  it,  and  only 


DERMOID  SYSTEM. 


561 


slightly  yellowish.  It  is  not  till  after  birth  that  a brown 
circle  surrounds  the  nails,  eyes,  nipples  and  genital  parts  ; 
‘on  the  third  day  these  parts  alone  are  black;  the  rest  of 
the  body  is  yet  only  tawny.  On  the  seventh,  the  colour 
is  general  though  pale,  and  continues  so  during  child- 
hood ; its  intensity  increases  gradually  in  the  adult  age, 
without  acquiring  however  the  same  shade  every w'here  ; 
the  parts  that  are  first  coloured  remain  generally  the  dark- 
est. These  successive  changes  which  are  also  observed 
in  the  other  races,  are  so  many  evident  proofs  of  the 
motion  of  which  the  colouring  matter  is  the  seat. 

This  matter  has  the  greatest  relation  with  that  which 
colours  the  hairs,  the  iris  and  the  choroid  coat ; thus  all 
these  parts  undergo  the  same  change  as  the  skin  when  it 
is  deprived  of  its  colour,  as  is  seen  in  albinos,  from  a de- 
fect of  organization. 

The  two  other  parts  of  the  mucous  body,  viz.  the 
horny  layer  and  the  epidermoid  membrane  of  the  papillae, 
or  the  two  whitish  layers  are  not  so  well  known  as  the 
coloured  layer.  These  layers  besides  being  apparent  in 
the  negro,  are  seen  under  many  circumstances.  Thus 
the  bulbs  of  the  hairs  exhibit  on  the  interior,  species  of 
flakes  which  appear  to  be  formed  by  the  epidermis  of 
the  papillae;  when  the  nail  is  separated  from  the  papillae 
which  are  below  it,  as  may  happen  from  a blow,  these 
papillae  are  covered  with  a concrete  matter  which  is 
nothing  else  than  this  epidermoid  layer.  The  horny 
layer,  by  its  extraordinary  development,  produces  all 
those  horny  productions  which  appear  on  the  skin,  either 
in  a natural  state,  as  the  horns  of  animals,  the  scales  of 
fishes  and  serpents,  the  nails,  &c.  or  in  the  state  of  dis- 
ease, as  the  horny  substances  which  sometimes’  arise  on 
the  skin  of  man  ; these  productions,  all  situated  below 
the  epidermis,  evidently  belong  to  the  la3^er  of  which  we 
are  speaking. 


262 


ADDITIONS  TO  THE 


The  sanguineous  bunches,  as  we  have  seen,  are  con- 
founded with  the  papillae  ; these  make  a part  of  the  der- 
mis or  chorion,  whose  external  face  they  occupy,  and 
ought  not  to  be  distinguished  from  them,  as  has  been 
done,  under  the  name  oi papillary  body.  Their  arrange- 
ment is  remarkable  ; the  rugae  which  they  represent  form 
regular  lines  separated  by  very  evident  furrows,  and,  in 
addition,  another  furrow,  not  so  deep  as  the  first,  but 
having  the  same  direction,  divides  each  of  these  lines 
near  its  summit  into  two  secondary  elevations,  so  that 
when  the  skin  is  cut  across  perpendicularly  to  the  direc- 
tion of  these  lines,  the  species  of  curved  thread  which  is 
seen  along  the  divided  edge  exhibits  undulations  alter- 
nately large  and  small  ; it  follows  from  this  arrangement 
that  each  prominent  line,  simple  at  its  base,  seems  to  be 
composed  at  its  summit  of  a double  row  of  papillae. 

The  structure  of  these  rugae  of  the  dermis  is  almost 
wholly  vascular  ; their  analogy  with  the  papillae  of  the 
tongue  and  the  phenomena  that  are  observed  in  them 
seem  to  prove  that  the  nerves  are  very  numerous,  and 
that  there  is  a peculiar  venous  arrangement,  analogous  to 
that  of  the  erectile  textures.  It  is  to  this  very  evident 
arrangement,  as  well  as  to  the  nervous  structure,  that  the 
papillae  of  the  tongue  owe  the  kind  of  erection  of  which 
they  appear  to  be  susceptible.  This  erection  is  evident 
in  the  tongue.  The  papillae  of  this  organ  are  soft,  flat- 
tened and  indistinct  at  the  period  of  digestion,  but 
straighten  up  and  become  more  apparent  during  masti- 
cation. Something  similar  is  seen  on  the  skin  of  the 
fingers  ; the  pulp  of  this  part  often  acquires  in  the  exer- 
cise of  touch,  a peculiar  firmness,  tension,  and  at  the 
same  time  redness. 

It  is  in  the  papillae,  that  most  of  the  phenomena  of 
vitality,  of  which  the  skin  is  the  seat,  take  place ; it  is 


DERMOID  SYSTEM. 


26S 


there  that  the  feeling  and  touch  are  exercised ; it  is 
there  that  all  the  parts  which  are  more  superficially  situ- 
ated are  secreted,  there  the  colouring  matter  is  formed, 
there  the  hairs,  nails,  feathers,  horns,  scales,  &c.  are 
produced.  We  cannot  be  astonished  then  at  the  quan- 
tity of  vessels  which  terminate  there  ; the  whole  capil- 
lary system  of  the  skin  is  brought  there  by  the  nature 
of  the  functions  which  they  perform.  This  idea  how- 
ever should  not  be  exaggerated,  and  it  must  not  be 
thought  that  there  are  vessels  nowhere  else,  that  the 
texture  of  the  chorion  more  deeply  situated  is  destitute 
of  them,  and  that  all  go  to  its  surface ; the  dermis  is 
often  injected  in  its  whole  thickness,  both  from  inflam- 
mation and  fine  injections  ; only  the  surface  seems  to  be 
more  so.  By  taking  from  a portion  of  injected  skin, 
rendered  transparent  by  immersion  in  the  oil  of  turpen- 
tine, a thin  strip,  cut  in  the  direction  of  the  thickness 
of  the  membrane,  and  by  examining  it  against  the  light, 
we  do  not  see  in  it  more  vessels  on  the  external  than  the 
internal  side.  Finally,  if  all  the  vessels  of  the  dermis 
were  contained  in  a superficial  layer,  we  might,  by 
scraping  the  external  surface  of  a portion  of  injected 
skin,  destroy  these  vessels,  and  remove  from  the  dermis 
almost  all  its  red  colour ; now,  this  cannot  be  done. 

Cutaneous  Msorption. 

Page  298. — “ Many  modern  philosophers  have  pro- 
duced numerous  negative  facts  against  cutaneous  absorp- 
tion.” 

This  absorption  is  much  less  marked  than  that  of  the 
mucous  membranes  ; it  is  not  in  fact  evident  unless  there 
is  friction  or  excitement  of  the  skin,  by  which  the  epi- 


ADDITIONS  TO  THE 


I>(i4 

dermis  is  opened,  raised  up,  or  in  part  detached,  and  It 
does  not  appear  to  take  place  from  mere  contact ; at 
least  there  are  more  facts  against  than  in  favour  of  this 
last  mode  of  absorption.  Bichat  explains  these  facts 
vvhich  are  apparently  in  contradiction  to  those  in  which 
the  absorption  is  evident,  by  the  varieties  of  sensibility 
vvhich  the  skin  exhibits  ; but  he  has  not  made  the  dis- 
tinction which  we  hav^e  just  established,  and  it  is  easy  to 
observe  that  it  is  when  the  skin  is  only  in  mere  contact 
with  the  substance  subjected  to  its  absorption,  that  this 
is  the  most  doubtful.  Thus  water  applied  on  the  sur- 
face of  the  integuments  most  usually  is  not  absorbed,  as 
Bichat  had  already  remarked,  and  Symson,  who  pretends 
that  he  has  seen  a foot-bath  sensibly  diminished  after  it 
had  been  used  b)''  a patient,  has  been  contradicted  by  all 
those  who  have  since  repeated  the  experiment.  That  of 
IMascagni,  in  which  the  inguinal  glands  are  swelled  under 
the  same  circumstances,  is  but  an  insulated  fact,  and  one 
which  besides  may  not  be  owing  to  the  absorption  of  the 
liquid.  It  is  indeed  said,  that  by  holding  one  hand  im- 
mersed in  a vessel  of  mercury,  and  by  having  in  the 
other  a piece  of  any  metal  that  is  susceptible  of  being 
attacked  by  it,  as  gold  or  silver,  the  latter  blackens,  pre- 
cisely as  if  it  were  in  direct  contact  with  the  mercury  j 
whence  it  has  been  inferred,  that  the  mercury  was  ab- 
sorbed on  one  side  and  then  carried  into  the  blood,  which 
afterwards  transmitted  it  to  the  opposite  side  ; but  is  the 
fact  certain,  and  have  all  these  circumstances  of  it  been 
observed  ? Some  experiments,  made  with  the  greatest 
accuracy  by  Dr.  Rousseau  of  Philadelphia,  prove  on  the 
contrary,  that  t!ie  essential  oil  of  turpentine,  the  absorp- 
tion of  which  is  so  rapid  by  the  mucous  surfaces,  as  we 
know,  does  not  produce  in  the  urine  that  characteristic 
odour,  the  unequivocal  indication  of  its  absorption,  when 


DERMOID  SYSTEM. 


265 


it  is  merely  applied  upon  the  skin,  taking  care  not  to 
allow  it  to  be  introduced  by  respiration.  Before  we 
admit  this  absorption,  let  us  wait  till  new  experiments 
have  demonstrated  the  reality  of  the  absorption  by  sim- 
ple contact. 

As  to  the  iri’egularity  which  Bichat  attributes  also  to 
the  other  species  of  absorption,  founded  upon  this,  that 
the  insertion  of  virus  is  not  always  followed  with  success, 
it  is  possible  in  fact  that  the  virus  may  not  be  absorbed  in 
this  case ; but  we  should  be  careful  not  to  confound  its 
passage  into  the  blood  with  its  apparent  effect,  especially 
when  this  effect  is  purely  local,  the  first  might  very 
well  take  place,  and  the  other  not  exist. 

The  same  remark  is  applicable  to  what  most  authors 
say  respecting  the  greater  facility  of  absorption  during 
sleep,  hunger,  &c.  and  in  general  in  all  the  states  which 
dispose  to  weakness.  Contagious  and  other  miasmata 
are  perhaps  more  active  under  these  circumstances  only 
from  the  greater  susceptibility  of  the  organs. 

Some  authors  have  spoken  of  a gaseous  absorption 
which  is  constantly  taking  place  upon  the  integuments, 
and  the  result  of  which  they  have  endeavoured  to  esti- 
mate ; according  to  others,  the  skin  is  the  seat  of  an  exha- 
lation of  the  same  nature.  It  is  evident  that  if  these  two 
functions  exist  there,  their  effect  must  be  confounded, 
and  that  it  is  impossible,  by  collecting  the  gases,  the 
atmospheric  air,  for  example,  which  may  have  remained 
on  the  surface  of  the  skin,  to  distinguish  if  the  changes 
of  proportion  that  are  observed  in  them  are  owing  to  a 
diminution  of  some  of  their  principles  or  to  an  increase 
of  the  contrary  ones,  and  consequently  to  determine 
what  belongs  to  exhalation  and  what  to  absorption.  It  is 
then  incorrect  to  say,  as  Fourcroy  has  done,  that  the 
skin  gives  out  azote ; the  nature  of  this  exhalation,  if  it 
34 


266 


additions  to  the 


takes  place,  is  very  difficult  to  be  determined.  Besides, 
the  proof  which  Fourcroy  has  given  of  its  existence, 
drawn  from  the  bubbles  that  are  disengaged  from  the 
surface  of  the  body  when  it  is  immersed  in  a bath,  does 
not  appear  to  me  to  be  substantial.  These  bubbles  are 
nothing  but  the  air  which  adheres  to  the  integuments  and 
which  has  become  rarefied  by  the  heat  of  the  bath  ; when 
all  this  air  has  once  escaped,  the  disengagement  ceases  ; 
these  bubbles  are  not  seen  to  form  in  the  cold  bath,  the 
air  not  having  there,  from  the  want  of  dilatation,  the  same 
tendency  to  quit  the  surface  of  the  skin. 

Sebaceous  Glands. 

Page  307. — ‘‘  There  is  I think  as  much  probability  in 
the  supposition  of  the  exhalation,  as  of  that  of  the  secre- 
tion of  the  cutaneous  oil.” 

I 

The  existence  of  the  sebaceous  glands  or  follicles  of 
the  skin  is  proved  by  the  following  considerations,  which 
have  been  already  in  part  stated  in  the  article  upon  the 
mucous  glands. 

1st.  'T’hese  glands  are  apparent  in  many  places,  as  on 
the  nose,  the  forehead,  the  hairy  scalp,  around  the  lips, 
in  the  hollow  of  the  axilla,  in  the  groin,  in  the  neighbour- 
hood of  the  nipples  and  arms,  and  in  general  wherever  the 
cutaneous  oil  is  secreted  in  great  quantity.  M.  Gaultier 
asserts  that  the  bulbs  of  the  hairs  are  surrounded,  at 
their  orifice,  by  nine  sebaceous  follicles  destined  to 
furnish  the  oily  matter  which  lubricates  them. 

2d.  These  glands  are  very  variable  in  their  size,  and 
there  are  subjects  in  whom  they  do  not  seem  to  exist  in 
certain  parts,  in  which  they  are  found  very  large  in 
others  ; so  that  by  thus  collecting  together  all  the  insulat- 


DERMOID  SYSTEM. 


267 


ed  observations,  there  is  perhaps  no  part  of  the  skin  in 
which  they  may  not  have  been  met  with. 

3d.  They  often  appear  suddenly  where  they  were  not 
before  distinct,  and  even  acquire  so  great  a size  as  to 
constitute  a real  disease.  It  is  not  probable  that,  in  this 
case,  these  glands  are  formed  all  at  once  ; their  arrange- 
ment is  too  similar  to  what  they  exhibit  in  the  places 
where  they  are  naturally  observed. 

4th.  The  same  substance  everywhere  covers  the  sur- 
face of  the  skin ; the  organs  which  furnish  it  must  then 
be  generally  distributed.  Now  the  sebaceous  follicles 
are  evidently  these  organs,  in  the  parts  where  they  dis- 
tinctly exist. 

It  may  then  be  accurately  deduced  from  all  this,  that 
the  sebaceous  glands  exist  everywhere,  and  that  their 
tenuity  alone  often  prevents  them  from  being  perceived  ; 
that  consequently  the  oily  fluid  of  the  skin  is,  as  is  gen- 
erally thought,  the  product  of  a secretion. 

The  structure  of  these  glands  is  analogous  to  that  of 
the  mucous  glands,  which  we  have  described  ; the  skin 
folded  upon  itself  appears  in  general  to  constitute  them. 
The  membrane  which  forms  them  is  continued  with  the 
dermis  ; the  epidermis  is  very  apparent  in  the  tumours 
which  result  from. their  dilatation  ; these  tumours,  when 
cut  open  and  emptied  of  the  matter  they  contain,  are 
evidently  covered  on  the  interior  by  an  epidermis,  which 
is  detached  from  them  by  maceration  with  that  of  the 
neighbouring  skin.  The  horny  layer  itself  is  indicated 
in  these  follicles  by  the  productions  of  that  kind  which 
are  sometimes  developed  in  them  ; in  fact,  hairs  have 
been  seen  to  derive  their  origin  from  them,  and  horns 
to  arise  in  them  and  push  out  through  their  orifices  ; the 
coloured  layer  is  also  evident  in  them  under  some  cir- 
cumstances. 


26S 


ADDITIONS  TO  TIIE 


MORBID  ANATOMY  OP  THE  DERMOID  SYSTEM. 


I.  Alterations  in  the  External  Forms. 


The  skin  when  distended  experiences  various  changes. 
(Vide  Vol.  3d.  Properties  of  Texture  of  the  Dermoid 
System.)  When  it  is  so  for  a long  time,  the  fibres  of 
the  dermis  are  not  only  separated,  hut  they  are  broken 
in  various  places  ; hence  the  whitish  striae  of  the  skin  of 
the  abdomen  of  women  who  have  been  once  or  many 
times  pregnant ; these  striae,  often  important  in  legal 
medicine,  because  they  are  constant,  are  real  cicatrices. 
When  the  distension  has  been  many  times  repeated  or 
carried  very  far,  the  skin  having  lost  in  part  its  tendency 
to  contract,  becomes  larger  than  is  necessary  to  cover 
the  subjacent  parts,  and  remains  loose  and  soft,  or  forms 
folds,  as  is  seen  on  the  skin  of  the  abdomen  ; it  is  the 
same  phenomenon  as  that  which  produces  the  wrinkles 
in  old  people  who  become  emaciated,  as  has  been  said 
elsewhere.  Besides,  the  skin  varies  in  this  respect  in 
different  individuals  ; one  woman,  after  the  first  preg- 
nancy, has  the  abdominal  parietes  more  loose  than  those 
of  another,  whose  abdominal  parietes  remain  smooth  and 
uniform,  though  she  may  have  had  many  children.  Age 
has  also  much  influence  upon  it.  The  same  differences 
exist  in  diseases,  when  a tumour,  for  example,  has  vio- 
lently separated  the  skin  of  the  neighbouring  textures  ; 
hence  the  modifications  to  be  observed  with  regard  to 
the  quantity  of  the  skin  to  be  left,  when  these  tumours 
are  removed,  according  to  the  age,  sex,  idiosyncrasy, 
size,  duration  of  the  tumour,  &c. 


DERMOID  SYSTEM. 


36» 


The  surface  of  the  skin  is  deformed  by  many  produc- 
tions of  a very  different  nature.  Some  are  the  evident 
product  of  inflammation  ; they  will  be  noticed  hereafter. 
The  others  constitute  peculiar  degenerations,  and  will 
also  be  presently  examined.  But  there  are  some  which 
seem  to  depend  only  on  a preternatural  increase  of  some 
one  of  the  layers  of  which  the  skin  is  composed.  Thus 
the  horny  layer  is  raised  up  upon  the  integuments  in  the 
form  of  hard  excrescences,  in  every  respect  similar  to 
horns  ; the  vascular  net-work  of  the  papillae  raises  the 
delicate  epidermis,  and  produces  exuberances  more  or 
less  red,  such  as  the  growths  from  syphilis  ; the  substance 
of  the  dermis  itself  grows  and  is  produced  on  the  surface 
and  forms  warts. 

The  horny  productions,  respecting  which  there  are 
many  observations  in  existence,  do  not  depend  simply 
on  the  cause  that  we  have  just  pointed  out ; they  may  be 
divided  into  three  kinds.  1st.  In  consequence  of  wounds 
and  ulcers,  there  is  often  formed  upon  the  cicatrices 
productions  of  this  nature.  2d.  The  sebaceous  follicles 
are  also  sometimes  the  origin  of  these  horns,  of  which  Sir 
Astley  Cooper  and  Sir  Everard  Home  have  given  exam- 
ples ; they  have  then  concentric  layers  such  as  are  seen 
in  trees.  3d.  Finally,  there  are  horns  which  arise  irregu- 
larly upon  all  parts  of  the  skin,  and  which  cannot  be 
referred  to  either  of  the  two  preceding  species  ; these 
are  those  especially  which  seem  to  have  their  seat  in  the 
horny  layer  of  the  skin,  and  to  be  nothing  else  than 
a more  copious  secretion  of  this  layer,  from  the  irrita- 
tion of  the  subjacent  papillae.  Corns  on  the  feet  are 
from  a very  similar  source  ; they  are  formed  by  a small 
hard  round  body,  arising  from  the  horny  substance  of 
the  skin,  and  covered  by  the  laminae  of  the  epidermis  ; 
only  this  species  of  horny  matter  is  forced  by  pressure 


270 


ADDITIONS  TO  THE 


into  the  substance  of  the  dermis,  and  sometimes  even 
below  it,  instead  of  growing  on  its  surface. 

The  enlargement  of  the  sebaceous  follicles  of  the  skin 
produces  a peculiar  kind  of  tumours.  When  this  en- 
largement is  inconsiderable,  the  tumour,  hardly  percepti- 
ble, is  discoverable  on  the  surface  of  the  skin  only  by  a 
black  point,  from  which  can  be  pressed  out  the  sebaceous 
matter  contained  in  it,  and  taking  the  form  of  the  aper- 
ture of  the  follicle,  escapes  under  the  form  of  a small 
worm,  and  has  even  been  sometimes  taken,  on  this 
account,  for  the  larva  of  an  insect ; this  black  point  is 
owing  to  the  particles  which  float  in  the  air  and  which 
soil  the  entrance  of  the  follicle.  When  the  matter  is 
accumulated  in  greater  quantity,  the  tumour  is  more 
prominent,  and  constitutes,  according  as  the  orifice  of 
the  follicle  is  open  or  not,  those  pimples,  so  common 
on  the  face,  on  the  skin  of  the  nose  especially,  or  the  sub- 
cutaneous wens  that  are  seen  in  the  various  parts  of  the 
body.  These  never  depend  on  any  other  cause  ; all 
those  pretended  meliccris,  atheromas  and  steatomas, 
which  are  developed  on  the  head,  under  the  hairy  scalp, 
in  the  sub-cutaneous  cellular  texture  of  the  extremities, 
thorax  and  abdomen,  and  which  differ  only  in  the  degree 
of  consistence  of  the  matter  which  they  contain,  as  their 
names  imply,  are  at  first  situated  in  the  substance  of  the 
skin,  as  is  easily  proved  by  examining  them  in  their 
commencement.  There  may  be  often  observed  in  the 
same  subject  the  kind  of  gradation  which  these  tumours 
follow  in  their  progress,  that  is  when  there  are  many  of 
them  ; the  smallest  then  exhibit  an  opening  very  appa- 
rent on  the  surface  of  the  skin,  whilst  the  others  remove 
by  degrees  from  the  integuments,  to  which  they  are  still 
however  attached,  in  the  greatest  number  of  cases,  by  a 
hollow  filament,  which  is  the  neck  of  the  follicle  elon- 


DERMOID  SYSTEM. 


271 


gated  by  distension.  There  are  no  true  wens  but  the 
fatty  tumours.  Thus  the  substance  of  those  called  en- 
cysted perfectly  resembles  the  sebaceous  matter  of  the 
follicles  ; this  kind  of  tumours  have,  like  the  latter, 
an  internal  epidermis.  These  last  characters  would 
almost  alone  be  sufficient  to  establish  the  identity  of 
these  tumours  with  the  follicles,  if  their  connexion  with 
the  skin  in  the  beginning  could  not  be  demonstrated. 
The  opening  of  the  follicles,  instead  of  being  obliterated, 
is  sometimes  so  enlarged,  in  those  small  tumours  of  the 
skin  before  noticed,  that  the  bottom  of  them  is  almost 
completely  exposed  ; their  internal  surface,  in  contact 
with  the  air,  then  becomes  dry,  the  tumour  ceases'  to 
grow,  and  thei’e  remains  simply  in  the  place  it  occupied, 
a kind  of  cul-de-sac,  continuous  with  the  skin,  which 
appears  to  be  there  folded  up.  This  arrangement  renders 
the  structure  of  the  follicles  very  evident. 

The  whole  cutaneous  system  is  the  seat  of  a kind  of 
atrophy,  in  the  marasmus,  which  succeeds  slow  diseases ; 
in  this  case  the  colouring  matter  disappears,  the  dermis 
dries  and  is  thinner,  the  papillae  are  diminished  and  the 
skin  becomes  rough  from  the  prominence  of  the  bulbs 
of  the  hairs  which  are  below  it.  Opposed  to  this  state 
is  the  superabundance  of  life  so  common  in  the  integu- 
ments of  the  face,  especially  in  drunkards,  and  which 
is  shown  by  the  vascular  bunches  in  this  part.  A long 
continued  irritation  may  also  thicken  the  dermis,  as  is 
often  seen  around  old  ulcers. 

II.  iterations  in  the  Organization. 

Cutaneous  phlegmasias  form  a numerous  class  in  patho- 
logy ; but  their  infinite  shades  are  confounded  in  great 
measure  in  the  eyes  of  the  anatomist.  The  alterations 


ADDITIONS  TO  THI' 


of  texture  vvliich  they  jDroduce  in  the  skin  are  always 
nearly  the  same,  however  numerous  may  be  the  eruptions 
with  which  they  cover  it.  The  common  characters  of 
most  of  the  exanthemata,  both  acute  and  chronic  are  an 
increase  of  blood  in  the  capillary  net-work,  and  conse- 
quently a greater  development  of  this  net-work,  either 
generally,  or  in  points  more  or  less  precisely  insulated  ; 
a fluid  difl’ering  from  the  blood  raising  up  the  epidermis 
or  spread  on  its  surface  and  forming  there  various  kinds 
of  scabs  ; the  epidermis  itself  in  various  ways  altered  and 
its  regular  production  often  prevented.  These  aflfections 
do  not  essentially  differ  except  in  the  degree  of  excite- 
ment which  produces  them,  the  different  structure  of  the 
skin  in  the  parts  which  they  occupy,  and  the  peculiar 
habit  of  the  persons  who  are  affected  with  them  ; all 
these  circumstances  produce  modifications  in  their  pro- 
ducts. Perhaps  however  this  subject  deserves  new  re- 
searches ; since  the  seat  of  these  diseases  in  the  cutaneous 
texture  does  not  appear  to  be  always  the  same  ; since 
tinea,  for  example,  seems  to  arise  more  especially  from 
the  sebaceous  follicles,  and  some  eruptions  appear  to  be 
confined  to  tbe  most  superficial  layers  of  the  skin,  whilst 
in  others  the  whole  substance  of  this  membrane  is  altered. 
In  general,  all  those  who  have  written  upon  the  diseases 
of  the  skin  are  more  engaged  in  describing  minutely  the 
forms  they  affect  upon  this  membrane,  than  in  investi- 
gating the  changes  they  produce  in  its  organization. 

Besides,  the  usual  effects  of  inflammation  have  been 
observed  in  the  skin.  It  suppurates,  not  only  when  its 
epidermis  is  removed,  as  from  a blister,  but  even  when 
its  texture  is  sound,  in  the  same  way  as  the  cellular  tex- 
ture ; the  pus  is  usually  in  small  cavities  which  raise  up 
the  epidermis,  as  is  seen  in  the  pustules  of  the  small  pox. 
Ulceration  is  frequent  in  this  membrane,  less  so  however 


DERMOID  SYSTEM. 


S73 


than  in  the  mucous  system  ; it  is  sometimes  connected 
with  suppuration,  as  is  commonly  observed  in  the  small 
pox ; at  other  times  it  is  the  effect  of  a peculiar  cause, 
such  as  syphilis.  It  is  necessary,  moreover,  to  distin- 
guish those  cases  in  which  ulceration  proceeds  from 
without  inwards,  from  those  in  which  the  skin  is  dis- 
tended, at  first  only  becomes  thinner  and  is  finall}'  in- 
flamed and  destroyed,  from  within  outwards,  as  takes 
place  in  abscesses,  aneurisms,  &c. 

Simple  wounds  of  the  skin  heal  quickl}^,  and  without 
the  formation  of  fleshy  granulations.  A plastic  layer, 
analogous  to  that  which  is  formed  between  the  other 
divided  textures,  and  which  M.  Brachet  has  found  to  be 
composed  of  gelatine  and  albumen,  reunites  at  first  weakly 
the  edges  of  the  wound,  which  can  in  the  beginning  be 
separated  afresh,  without  giving  hardly  any  pain,  or 
occasioning  the  flow  of  blood,  with  which  this  layer  is 
not  yet  penetrated.  Vessels  are  afterwards  produced  in 
this  substance,  which  at  the  same  time  acquires  more 
consistence,  and  the  cicatrix  is  complete.  This  cicatrix  is 
soon  confounded  with  the  texture  of  the  skin,  from  which 
it  finally  cannot  be  distinguished. 

The  phenomena  are  also  very  simple  when  the  skin  is 
destroyed  only  in  its  superficial  layers,  and  the  dermis  is 
merely  denuded  ; the  epidermis  is  then  reproduced  with 
great  rapidity  over  the  whole  extent  of  the  wound  ; this 
is  what  is  seen  in  blisters,  burns  of  the  second  degree, 
slight  excoriations,  &c.  If  however  thei  rritation  is  great, 
as  in  a burn,  suppuration  comes  on,  and  the  cure  is  not 
so  speedy  ; but  fleshy  granulations  are  not  formed  unless 
the  suppuration  is  long  continued,  as  in  blisters. 

On  the  contrary,  these  granulations  exist  necessarily 
when  there  is  a complete  loss  of  substance  of  the  skin, 
and  the  lips  of  the  wound  remain  separate ; they  always 
35 


274 


ADDITIONS  TO  THE 


precede  in  this  case  the  formation  of  the  cicatrix,  which 
then  arises  from  the  various  textures  laid  bare,  particu- 
larly from  the  cellular. 

The  skin  is  but  little  subject  to  organic  transforma- 
tions. It  acquires  under  some  circumstances  all  the  char- 
acters of  the  mucous  membranes;  this  takes  place,  when 
it  is  long  in  contact  with  itself  and  deprived  for  a length 
of  time  of  the  air  on  its  exterior ; a less  thickness  of  the 
dermis,  a greater  redness  of  its  surface,  which  continually 
pours  out  a copious  mucous  fluid,  and  an  extreme  delicacy 
of  the  epidermis,  covered  with  very  distinct  villi,  are 
observed  in  this  case,  an  example  of  which  is  cited  by 
Hribreard  in  which  this  alteration  was  produced  in  the 
hollow  of  the  ham,  in  a paralytic  patient,  by  the  constant 
flexion  of  the  leg  upon  the  thigh.  We  have  seen,  in  the 
Cartilaginous  System,  that  the  skin  sometimes  experiences 
the  cartilaginous  transformation. 

The  cancer  of  the  skin  assumes  a peculiar  form  which 
is  only  observed  in  this  membrane  and  in  the  mucous 
system ; it  constitutes  most  often  ulcerations  around 
which  the  neighbouring  texture  is  little  altered,  so  that 
in  an  anatomical  view,  there  is  no  resemblance  between 
these  ulcers  called  carcinomatous  and  the  other  cancer- 
ous affections.  There  arises  also  upon  the  integuments, 
in  some  cases,  excrescences  analogous  to  the  cancerous 
polypi  of  the  mucous  membranes.  In  the  sub-cutaneous 
cancerous  tumours,  the  skin  is  subsequently  affected  in 
two  different  ways  ; sometimes  it  contracts  a very  great 
consistence,  a remarkable  kind  of  hardness  at  the  same 
time  that  it  adheres  intimately  to  the  parts  which  it 
covers  ; sometimes  it  ulcerates  from  within  outwards,  as 
takes  place  in  the  ordinary  termination  of  cancer. 


DERMOID  SYSTEM. 


27B 


III.  Alterations  in  the  Development. 

The  defects  of  conformation  of  the  Dermoid  System, 
are,  1st,  absence  of  the  skin  to  a certain  extent,  where 
it  usually  is  found,  which  is  scarcely  ever  seen  unless 
there  is  at  the  same  time  a want  of  the  subjacent  parts, 
as  when  the  cavities  of  the  mucous  membranes  exhibit 
preternatural  openings  ; 2d,  various  elongations  which  the 
texture  of  the  skin  forms,  and  with  which  the  surface 
of  this  membrane  is  covered  ; 3d,  the  spots  from  birth 
or  nsevi  materni ; these  are  sometimes  merely  an  altera- 
tion of  the  colouring  matter,  sometimes  an  affection  of 
the  vascular  net-work,  and  most  often  become  in  the 
latter  case  after  birth,  tumours  that  are  called  varicose^ 
and  which  have  much  analogy  with  the  erectile  textures. 
The  spots  are  often  covered  with  hairs. 

New  integuments  are  preternaturally  produced  when- 
ever the  parts  naturally  covered  by  the  skin  are  deprived 
of  this  common  coveting,  as  after  wounds,  ulcers,  ab- 
scesses, gangrene,  &c.  ; the  new  texture  which  is  formed 
under  these  circumstances  constitutes  the  cicatrix.  I 
would  observe,  upon  this  subject,  that  this  word  serves  to 
designate  all  the  modes  of  union  which  take  place  be- 
tween divided  parts ; now  there  is  a number  of  these 
modes,  and  consequently  several  species  of  cicatrices. 
1st.  There  are  those  which  succeed  the  internal  ruptures 
which  various  organs  experience,  the  skin  which  covers 
them  remaining  sound  ; those  of  the  different  systems 
have  been  examined  under  each  one  of  them  in  particu- 
lar ; we  have  seen  that  they  partake  in  general  more  or 
less  of  the  textures  in  which  they  are  situated,  though  an 
analogous  cause,  an  exudation  of  a substance  capable  of 


ADDITIONS  TO  THE 


276 

concretion,  most  often  presides  over  their  formation  in 
tlie  beginning.  There  are  no  flesi^y  granulations  when 
these  cicatrices  are  completed.  2d.  The  union  of  wounds 
by  the  first  intention  furnislies  a second  kind  of  cica- 
trices, which  has  great  resemblance  to  the  preceding,  and 
which  only  differ  from  them  in  this,  that  the  divided  tex- 
tures communicate  at  first  on  the  exterior,  a circumstance 
which  their  mutual  contact  soon  renders  nothing,  so  that 
this  case  is  then  the  same  as  the  first.  The  skin  and  the 
cellular  texture  perform  the  greatest  part  in  this  union, 
which  is  effected,  like  the  preceding,  without  the  pro- 
duction of  fleshy  granulations.  3d.  Finally,  cicatrization 
properly  so  called  is  the  mode  of  cure  of  wounds,  and, 
in  general,  of  all  solutions  of  continuity  that  are  apparent 
on  the  exterior,  whose  neighbouring  edges  remain  sepa- 
rate, whether  because  they  have  suffered  too  great  a loss 
of  substance,  or  because  the  effects  of  contractility  of  tex- 
ture have  not  been  prevented,  or  because  the  structure  of 
these  edges  renders  their  approximation  impossible,  as  in 
wounds  of  the  bones.  There  is  in  this  case,  the  only  one 
which  w'e  should  notice  here,  suppuration,  formation  of 
fleshy  granulations,  and  consequently  of  a membrane 
analogous  to  the  skin.  This  membrane  is  everywhere 
the  same,  whatever  may  be  the  denuded  texture,  as  is 
proved  by  the  homogeneous  cicatrices  which  succeed 
amputations,  wounds  of  the  cranium  and  the  thorax,  in 
which  parts  of  a very  difierent  nature  are  concerned  ; the 
cartilages  are  the  only  organs  which  do  not  contribute 
to  its  formation. 

Two  periods  may  be  distinguished  in  the  cicatrization 
of  a wound ; 1st,  the  wound  is  covered  with  fleshy  granu- 
lations ; 2d,  an  epidermis  is  formed  upon  these  granula- 
tions, to  give  origin  to  the  cicatrix.  It  would  be  easy  to 
show  that  there  is  a greater  number  of  these ; but  these 


DERMOID  SYSTEM. 


277 


are  sufficient  to  give  an  idea  of  the  mechanism  of  the 
production  of  the  cicatrices.  These  periods  are  described 
in  Bichat,  Vol.  1st.  We  shall  now  pass  them  rapidly 
in  review. 

First  Period.  The  small  bodies  so  improperly  called 
fleshy  hunches,  and  which  have  also  been  known  by  the 
name  of  caruncles,  granulations  and  cellular  and  vas- 
cular hunches,  arise  in  proportion  as  suppuration  is 
established,  but  with  a different  rapidity  in  the  different 
textures  ; in  an  amputation,  for  example,  they  are  de- 
veloped in  the  first  place  upon  the  cellular  texture  which 
occupies  the  interstices  of  the  other  parts,  in  the  second 
place  on  the  surface  of  the  divided  muscles,  soon  after  on 
the  fibrous  organs,  and  still  later  in  the  bones,  most  often 
in  these  last  not  until  a delicate  lamina  is  detached  from 
them  ; in  general  they  are  produced  so  much  the  quicker 
as  the  textures  are  more  cellular  and  vascular.  The  size 
of  these  bunches  varies  ; their  arrangement  is  so  much 
the  more  regular  in  proportion  as  they  are  smaller,  and 
the  cicatrization  of  them  is  also  quicker.  The  membrane 
which  they  form  by  their  union  has  below  it  a compact 
cellular  texture,  appearing  as  if  penetrated  with  concrete 
albuminous  fluids.  This  membrane  contains  blood  ves- 
sels, for  the  bunches  bleed  from  the  least  touch,  and  red- 
den or  become  pale  from  various  causes.  The  absorbents 
are  not  demonstrated  in  it,  except  b)''  the  absorption 
which  these  bunches  perform,  and  by  the  ulceration  to 
which  these  are  so  disposed,  that  often  by  a deviation  in 
regimen,  they  totally  disappear  in  less  than  two  hours 
from  the  surface  of  a wound  ; their  extreme  sensibility 
leads  to  the  belief  that  there  are  nerves  in  it,  though  they 
have  never  been  seen.  The  membrane  of  the  fleshy 
bunches  is  endowed  with  a veiy  evident  contractility, 
-which  explains  the  real  contraction  and  diminution  of 


278 


ADDITIONS  TO  THE. 


wounds,  which  is  so  much  the  more  evident  as  the  skin 
is  at  the  same  time  more  moveable  and  extensible.  The 
cellular  nature  of  this  membrane  has  been  demonstrated 
elsewhere  ; many  authors  consider  it,  with  Fabrus,  as  a 
mere  extension  of  the  cellular  texture;  but  the  opinion 
of  Hunter,  which  has  been  more  fully  explained  by  Home, 
is  more  probable.  This  opinion,  which  I have  given  in 
the  Additions  to  the  Cellular  and  Capillary  Systems,  con- 
sists in  considering  it,  not  as  a preexisting  cellular  tex- 
ture, but  as  a new  production,  not  being  able  to  be  formed 
except  where  there  are  cellular  texture  and  blood  vessels, 
and  exhibiting  in  its  development  phenomena  analogous 
to  those  of  the  natural  development  of  the  organs. 

Second  Period.  When  the  fleshy  bunches  have  re- 
tracted as  much  as  the  resistance  of  the  integuments  in 
the  neighbourhood  of  the  wound  will  allow,  they  are  cov- 
ered with  epidermis,  which  constitutes  the  second  period 
of  cicatrization,  the  formation  of  the  cicatrix.  The  new 
epidermis  begins  to  be  formed  at  the  circumference  of  the 
wound,  where  it  is  evidently  continued  with  the  neigh- 
bouring epidermis,  and  afterwards  advances  by  degrees 
towards  its  centre  ; sometimes,  as  in  large  ulcers  of  long 
standing,  it  is  produced  at  the  same  time  in  small  parti- 
cles in  the  middle,  and  the  various  points  afterwards 
unite  together  ; the  pus  ceases  to  be  secreted  in  propor- 
tion as  the  epidermis  is  formed.  The  cicatrix  is  com- 
plete when  the  whole  extent  of  the  wound  is  covered 
with  epidermis.  This  cicatrix,  delicate  at  first,  soft,  red- 
dish on  account  of  the  want  of  thickness  of  the  epidermis 
which  covers  it,  more  adherent  and  less  solid  than  the 
skin,  finally  becomes  completely  analogous  to  this  mem- 
brane. The  cellular  texture  which  is  below  it  regains  by 
degrees  all  its  extensibility,  unless  the  cicatrix  rest  upon 
a bone  ; in  this  case  it  remains  adherent. 


DERMOID  SYSTExM. 


279 


The  new  cutaneous  texture  when  perfectly  developed, 
exhibits  the  following  characters.  1st.  This  texture  is 
more  dense  than  that  of  the  skin  and  has  a greater  resem- 
blance to  the  fibrous  textures  ; fewer  blood  vessels  enter 
it,  hence  the  white  colour  of  the  cicatrices  and  the  rare- 
ness of  their  preternatural  redness.  2d.  The  dermis, 
which  is  met  with  in  it,  has  less  evident  afeolse,  and  less 
distinct  fibres  and  lamina3  than  that  of  the  skin  ; this  der- 
mis is  in  general  destitute  of  papillae,  as  the  smooth  and 
shining  appearance  of  its  surface  indicates.  Sd.  The 
epidermis  is  very  apparent  in  cicatrices,  and  is  confound- 
ed with  that  of  the  surrounding  skin.  4th.  Camper  has 
denied  the  existence  of  the  mucous  body  in  it ; but  this 
body  is  demonstrated  there,  in  negroes,  by  the  colour 
of  which  their  cicatrices  are  the  seat.  This  colour  exists 
in  almost  all  cases  ; only  a sufficient  length  of  time  is  re- 
quired for  it  to  be  developed,  and  the  tint  it  assumes  is 
almost  always  paler  than  that  of  the  integuments;  how- 
ever in  some  rare  cases,  this  tint  has  been  seen  of  a 
deeper  colour.  The  horns  which  arise  upon  the  cicatrices 
indicate  in  them  the  presence  of  the  horny  layer.  5th. 
The  texture  of  the  cicatrix  is  more  disposed  to  ulcerate 
than  the  skin  properly  so  called  ; ulcers  which  affect  at 
the  same  time  these  two  membranes  make  much  more 
rapid  progress  in  the  first  than  in  the  second. 


ADDITIONS 

TO  THK 

EPIDERMOID  SYSTEM. 


Means  of  union  of  the  Epidermis  with  the  Dermis, — 
Exhalant  and  Absorbent  Pores. 

Page  351. — By  separating  the  epidermis  by  macera- 
tion; which  is  the  most  proper  means,  we  see  on  its  in- 
ternal surface  many  small  elongations  of  greater  or  less 
length,  and  which,  when  examined  attentively,  appear  to 
be  nothing  but  the  broken  extremities  of  exhalants  and 
absorbents.  In  fact  these  little  elongations  . . . have  all 
of  them  an  oblique  course,  and  terminate  in  the  pores 
which,  we  have  said,  pass  through  the  epidermis  to  go  to 
its  surface.” 

The  nature  of  the  elongations  which  are  intermediate 
between  the  dermis  and  the  epidermis,  and  which  can 
only  be  seen  by  separating  these  two  parts  from  each 
36 


2S2 


ADDITIONS  TO  TH^ 


other,  is  not  easily  ascertained.  Kaavv  Boerhaave  and 
W.  Hunter  maintained,  which  is  nearly  the  opinion  of 
Bichat,  that  they  were  the  vessels  of  the  sweat  or  the 
cutaneous  transpiration.  But  injections  do  not  reach 
these  elongations  ; inflammation,  which  renders  the  whole 
skin  vascular,  does  not  colour  them  sensibly.  Cruik- 
shank  considers  these  filaments  as  epidermoid  substance 
which  has  dipped  down  into  the  areolse  of  the  dermis. 
But  do  these  elongations  really  exist  when  the  epidermis 
is  adherent  to  the  dermis  ? Nothing  proves  it.  They 
sliould  rather  be  considered  as  species  of  mucous  tracts 
which  are  formed  by  the  separation  of  the  substance 
intermediate  to  the  dermis  and  the  epidermis,  rendered 
fluid  and  viscid  by  putrefaction  or  stewing  to  which  the 
skin  is  subjected  for  the  purpose  of  separating  the  epi- 
dermis. 

The  existence  of  the  pores  themselves,  such  at  least  as 
are  usually  represented  is  far  from  being  accurately  demon- 
strated. Physiological  considerations,  and  even  the  injec- 
tions of  Haase  would  lead  to  the  belief  that  the  openings 
of  the  vessels  go  to  the  last  layers  of  the  skin,  that  is  to 
say,  to  the  epidermis  ; but  microscopical  examination, 
which  is  more  worthy  of  confidence  than  physiological 
conjectures,  does  not  detect  pores  in  the  epidermis.  By 
examining  against  the  light  the  epidermis  of  a portion  of 
skin  from  which  the  greater  part  of  the  hairs  has  been 
removed,  there  is  seen  very  distinctly  transparent  places 
which  have  been  regarded  as  openings.  Leuwenhoeck 
thought  even  that  he  discovered  pores  in  the  epidermis, 
and  he  has  given  a drawing  of  them  in  his  JJrcana 
Nat}irs£.  But  as  this  great  observer  used  only  simple 
lenses,  which  magnify  but  about  a hundred  and  sixty 
times,  he  has  perhaps  mistaken  for  pores  the  foramina  of 
the  hairs.  Fontana,  in  his  work  upon  the  venom  of  the 


EPIDERMOID  SYSTEM. 


283 


viper,  speaks  of  a texture  composed  of  serpentine  vessels 
which  he  has  seen  by  the  aid  of  the  microscope;  but 
M.  de  Humboldt,  who  has  examined  the  human  epidermis 
with  a microscope  that  magnifies  35,200  times,  asserts 
that  the  serpentine  cylinders  are  folds  and  not  vessels  ; in 
some  observations  made  upon  the  epidermis  magnified 
312,400  times,  he  was  unable  to  discover  pores  in  it. 
I have  closed  the  extremity  of  a tube  with  a piece  of 
epidermis,  the  tube  containing  a column  of  mercury  of 
more  than  two  feet,  and  not  a particle  of  the  metal  passed 
through  the  epidermis. 

It  must  be  concluded  from  these  different  observations 
that  there  is  on  the  surface  of  the  skin  a non-vascular 
barrier  between  organization  and  the  atmosphere,  and  that 
whether  for  entrance  or  for  exit,  substances  must  pene- 
trate this  barrier  by  a sort  of  imbibition,  which  would 
approximate  this  extreme  part  of  the  organization,  to  the 
most  simple  bodies  of  either  organic  kingdom,  which  are 
destitute  of  vessels.  In  fact,  as  we  have  just  said,  there 
are  neither  vessels,  pores  nor  any  opening  discoverable 
by  the  microscope,  whether  the  oblique  insertion  of  the 
hairs  conceals  those  which  give  passage  to  them,  or 
whether  the  epidermis  furnishes  a sheath  for  them  which 
exists  after  their  removal  and  fills  the  foramina  with  which 
it  is  pierced.  We  cannot  however  deny  absolutely,  the 
existence  of  the  pores  from  microscopical  examination 
alone  ; for  if  we  make  a puncture  in  the  epidermis  with  a 
very  fine  needle,  we  cannot  discover  this  opening  by  the 
microscope,  as  Cruikshank  has  proved  by  experiment ; 
the  same  thing  takes  place  in  a very  delicate  lamina  of 
gum  elastic  or  caoutchouc,  in  which  a very  narrow  open- 
ing is  made ; on  the  contrary,  the  opening  continues 
when  perfectly  dry  epidermis  is  employed ; paper  that 
is  used  for  filtrating  presents  the  same  difference  accord- 


284 


ADDITIONS  TO  THE 


ing  as  it  is  dry  or  moist.  This  point,  which  has  been 
much  discussed  hy  authors,  does  not  appear  to  me  to  be 
yet  sufficiently  clear, 

Epidermis  of  the  Mucous  Membranes. 

Page  369. — “ What  is  the  place  in  which  the  epider- 
mis terminates  that  lines  the  origin  of  the  mucous  sur- 
faces, or  if  it  exists  everywhere,  where  does  it  begin  to 
become  no  longer  apparent  from  the  action  of  our  dif- 
ferent reagents  ? We  cannot,  I think,  determine  with 
precision  ; it  diminishes  in  an  insensible  manner,  and  is 
lost  as  it  were  by  degrees.” 

Bichat  leaves  here  two  questions  unsettled  ; the  first  is 
to  know  if  the  deep-seated  mucous  surfaces  have  an 
epidennis  ; and  the  second  is,  at  what  place  this  epider- 
mis ceases  or  changes  its  nature.  The  soft  and  pulpy 
state  of  the  deep-seated  mucous  membranes,  the  very 
great  resemblance  which  exists  between  the  composition 
of  the  mucus  and  that  of  the  epidermis,  and  the  presence 
of  villi  where  this  is  but  little  apparent,  lead  to  the  belief 
that  it  is  in  fact  wanting  in  deep-seated  parts.  On  the 
other  hand,  those  who  admit  its  existence  there  cite  the 
cases  of  inversion  of  the  rectum,  of  the  small  intestines  in 
preternatural  ani,  of  the  uterus,  &c. ; in  which  a distinct 
epidermis  covers  the  w'hole  of  these  parts  ; they  rely  also 
upon  the  membranous  excretions,  which,  according  to 
them,  have  no  other  source.  These  reasons  are  by  no 
means  decisive  ; there  is  no  proof  that  the  epidermis  of 
the  preternatural  ani,  for  example,  exists  originall}^,  and 
that  it  is  not  formed  afterwards  entirely  by  the  contact  of 
the  air.  As  to  the  membranes  voided  in  phlegmasias  of 
the  intestines,  the  bladder,  &c.  analogy  should  teach  us 


EPIDERMOID  SYSTEM, 


285 


to  regard  them  as  false  membranes  of  the  same  kind  as 
those  which  cover  under  the  same  circumstances  the  eye, 
the  mouth,  the  pharynx,  &c.  However  it  may  be  pos- 
sible that  a very  delicate  epidermis,  the  fineness  of  which 
would  render  it  still  more  difficult  to  be  perceived,  may 
be  found  upon  the  deep-seated  mucous  surfaces  ; this  first 
question  can  hardly  be  resolved  otherwise  than  it  has 
been  done  by  Bichat,  who  is  much  inclined  to  the  nega- 
tive. 

The  second  leads  to  something  more  positive.  In 
many  parts  of  the  mucous  system,  there  exists  a very 
evident  line  of  demarcation  between  the  portion  of  this 
system  placed  near  the  exterior  and  that  which  is  more 
deeply  situated.  This  line  is  owing  to  the  epidermis  of 
the  first,  which  ceases  w'here  the  second  begins.  Boil 
the  mucous  coat  of  the  stomach  and  that  of  the  oesopha- 
gus, the  epidermis,  raised  up  upon  the  latter,  will  soon  form 
a bunch  corresponding  exactly  with  the  cardiac  orifice, 
and  beyond  which  this  epidermis  will  cease  to  be  appa- 
rent. This  is  what  has  even  led  to  the  assertion  that 
there  was  at  this  place  an  interruption  in  the  mucous  sys- 
tem, and  that  the  mucous  membrane  of  the  stomach  was 
not  a continuation  of  that  of  the  oesophagus.  But  the 
epidermis  alone  forms  this  limit ; the  rest  of  the  mem- 
brane is  continued  perfectly.  This  is  so  true,  that  in 
animals,  the  line  of  demarcation  does  not  always  corres- 
pond with  the  cardiac  orifice,  and  often  this  line  en- 
croaches more  or  less  upon  the  stomach,  as  is  shown  in 
the  plates  of  Home,  in  which  it  is  seen  to  approach 
nearer  and  nearer  the  pyloric  orifice,  according  to  the 
species  of  animal.  It  is  the  same  case  with  the  mucous 
membrane  of  the  vagina  in  relation  to  that  of  the  uterus  ; 
its  epidermis  terminates  at  the  neck  of  this  viscus,  the 
interior  of  which  is  not  the  less  lined  by  a peculiar  mu- 


2S6 


ADDITIONS  TO  THE 


cous  membrane,  differing  from  the  first  only  in  having 
a less  degree  of  thickness  and  fewer  villi.  The  same  ar- 
rangement exists  at  the  neck  of  the  bladder,  as  is  proved 
by  the  experiment  noticed  above,  made  upon  this  viscus, 
and  the  urethra  which  is  inserted  into  it.  This  remark 
applies  in  general  to  all  the  mucous  ducts  which  open  on 
the  exterior,  and  terminate  in  a membranous  reservoir. 


Nature  of  the  Nails. 

Page  a 5. — “ We  cannot  consider  these”  (the  sails,) 
■‘‘as  mere  layers  of  epidermis  applied  to  each  other.” 

Malpighi  regarded  the  nails  as  the  consequence  of  the 
drying  of  the  papillaj  of  the  dermis.  Ludwig  said  that 
they  arose  from  the  dried  nervous  substance.  The  ex- 
amination of  the  horny  parts  of  animals  shows  that  they 
are  formed  by  a horny  substance,  of  the  same  nature  as 
that  which  constitutes  the  hoofs,  horns,  scales,  &c.  of 
various  animals.  The  epidermis  only  covers  these  parts, 
which  all  belong  to  the  horny  layer  which  is  subjacent 
to  it ; when  it  is  wanting  on  their  surface,  it  is  because 
friction  has  destroyed  it,  or  that  it  is  confounded  with 
their  superficial  laminae,  as  is  seen  particularly  with 
regard  to  the  nails. 

Considered  in  animals,  these  are  of  two  species.  1st. 
They  are  such  as  resemble  those  of  man,  these  are  the 
small  nails  [onguicules.  ) 2d.  Others  differ  from  them 

in  their  arrangement  have  received  the  name  of  nails 
{ongules) ; they  include  the  hoofs  of  various  quadrupeds. 
We  might  add  to  tliem  the  horns,  the  origin  of  which 
is  precisely  similar  to  that  of  the  nails  and  the  hoofs.  It 
is  necessary  however  to  distinguish  among  these  the  horns 


EPIDERMOID  SYSTEM. 


287 


of  deer,  and  the  horns  properly  so  called,  or  those  of 
ruminating  animals.  The  first  are  entirely  osseous,  and 
raise  up  the  skin,  instead  of  being  seated  on  the  surface 
of  this  membrane  ; the  second  alone  belong  to  this  sur- 
face ; only  they  usually  surmount  osseous  elongations,  to 
which  they  serve,  as  it  were,  for  sheaths.  The  nails  of 
man  are  not  coloured  ; those  of  animals  and  their  horns 
are  so  on  the  contrary  quite  often  ; their  colouring  matter 
appears  to  reside  in  general,  in  the  horny  substance 
itself. 

The  nails  and  the  horns  are  formed  by  the  same  me- 
chanism. When  a horn  is  torn  out  of  an  animal,  the 
papillae  in  a high  degree  vascular,  which  have  been  laid 
bare,  pour  out  a fluid  matter  which  can  he  seen  at  first 
to  rope  between  the  fingers,  if  we  may  be  allowed  the 
expression,  and  which  afterwards  thickens  and  hardens 
by  degrees  ; below  this  first  layer,  thei’e  is  formed  a 
second  which  raises  it,  and  then  a third,  and  thus  in  suc- 
cession, so  that  a new  horn  results  from  this  successive 
union  of  layers  ; this  horn  continues  to  grow  from  its 
base  in  the  same  manner,  the  new  layers  constantly  rais- 
ing the  old  ones.  Now  the  same  thing  is  observed  in 
the  hoofs,  as  also  in  the  reproduction  of  the  nails  of  man. 
The  form  alone  differs,  because  the  parts  secreting  the 
fluid  are  variously  formed.  When  the  nail  is  torn  out, 
the  papillse,  after  having  bled  copiously,  and  appearing 
bare  though  having  still  above  them  the  deep-seated 
whitish  layer,  are  covered  with  a soft,  white  lamina,  the 
consistence  of  which  gradually  increases  ; then  new 
laminae  are  produced  below,  so  much  shorter  as  they  are 
more  distant  from  the  root,  and  give  to  the  new  nail  the 
thickness  which  it  is  to  have  ; the  ulterior  growth  de- 
pends on  this,  that  the  horny  substance  is  continually 
poured  out  at  the  extremity  of  each  of  the  laminae,  which 


288 


ADDITIONS  TO  THE 


occasions  the  whole  of  the  nail  to  be  pushed  forward. 
This  mode  of  development  may  be  compared  to  that 
which  takes  place  in  the  silk  worm,  the  fluid  of  which 
is  constantly  reproduced  in  proportion  as  it  acquires  con- 
sistence, and  constantly  pushes  before  it  the  fluid  which 
has  preceded  it.  Thus  the  nail  would  grow  indefinitely 
if  it  were  not  habitually  cut,  or  worn  off  by  friction. 

The  longitudinal  striae  which  the  nails  exhibit  on  their 
surface  are  no  indication  of  a fibrous  structure  ; these 
striae  appear  to  depend  on  the  arrangement  of  the  sub- 
jacent papillae. 


MORBID  ANATOMY  OF  THE  EPIDERMOID  SYSTEM. 

The  parts  comprised  under  this  system  having  no  or- 
ganization, properly  speaking,  are  subject  to  but  a small 
number  of  alterations,  which  even  are  not  inherent  in 
them,  and  depend  only  on  the  changes  that  are  expe- 
rienced by  the  vitality  of  the  skin,  their  common  support. 
It  is  with  these  parts  as  with  the  different  fluids  that  are 
poured  out  upon  the  mucous,  serous,  synovial  surfaces, 
&c.  and  the  alterations  of  which  depend  entirely  on  those 
of  the  organs  which  furnish  them. 

The  epidermis  thickens,  becomes  thin,  is  raised  up  on 
the  surface  of  the  dermis  and  destroyed  by  various  causes, 
the  most  of  which  have  been  already  examined.  It  as- 
sumes the  form  of  vesicles,  blisters,  furfuraceous  scales 
and  large  plates,  when  it  is  raised  up  or  almost  entirely 
detached.  Its  reproduction,  usually  easy,  sometimes 
becomes  impossible  from  the  great  irritation  of  which  the 


EPIDERMOID  SYSTEM. 


289 


skin  is  the  seat,  as  in  a burn  or  chronic  pemphigus,  and 
then  the  patients  suflfer  much,  the  mucous  body  being 
bare.  At  other  times,  the  skin,  red  and  swelled,  furnishes, 
instead  of  the  fluid  which  produces  it,  a scabby,  crusty 
matter,  joined  to  a serous  fluid  which  oozes  out  copiously, 
as  is  seen  in  some  species  of  herpes. 

Tlie  excrescences  of  the  nails  are  especially  frequent 
in  the  dry  herpes,  in  which  the  skin  assumes  the  appear- 
ance that  has  been  compared  to  the  lichens  of  trees,  in 
which  the  epidermis  is  thickened  and  cracked  in  various 
directions.  They  come  upon  the  toes,  from  a cause  an- 
alogous to  that  which  produces  corns  upon  them.  In 
some  cases,  they  appear  to  be  owing  to  the  progress  of 
age. 

The  nails  become  soft  and  brittle  in  individuals  afiect- 
ed  with  scrophula  and  herpes.  They  exhibit  also  besides, 
in  some  cases,  a peculiar  alteration  which  authors  do  not 
appear  to  me  to  have  described.  It  consists  in  a sort  of 
chronic  inflammation  of  the  skin  which  surrounds  the 
root  of  the  nail ; a brown  circle,  painful  when  pressed, 
is  formed  at  this  place  ; the  nail  becomes  at  the  same 
time  thin  and  like  a membrane.  Buzzi  has  given  some 
examples  of  this  affection,  which  I have  many  times  ob- 
served in  children,  and  sometimes  in  adults. 

The  very  improper  expression  of  the  nail  growing 
into  the  flesh  serves  to  designate  a state  in  which  the 
skin  surrounding  the  nail  upon  the  edges  or  near  its 
extremity  goes  beyond  it  and  advances  more  or  less  upon 
the  free  face.  There  results  from  it  pains  more  or  less 
acute  by  the  pressure  which  the  cutting  edge  of  the  nail 
makes  upon  it.  This  inconvenience  hardly  ever  happens 
except  to  the  great  toe,  in  which  the  tightness  of  the 
shoes  often  produces  it.  The  extraction  of  the  nail  is 
the  most  efficacious  remedy  for  it. 

37 


- '-r-: 


:•  s;  ■ >. 


V ■ ’ ■.'  ,'  ' i<-  .f.l.*;;-,  , 


.JC(V'  ''Vi;,'!  ' , ,,•  , .,.,v 

' \-'V^Vr  ■■  ' ■ f '(j-ttif"','  ' 

• :'  :i:',;  ■ ■ _ ..,;v  Vvi \ \ < 

' ■“-  M 

'-■  . - ■ ■'  ''^v"  , 

'■  ' ,',  ■ iriV  ifV,.i  . ’4’'v7'^  .'-:i'J 


ADDITIONS 


TO  THE 


PILOUS  SYSTEM. 


Structure  of  the  Hairs. 

Page  401. — “ White  hairs  may  experience  vital  phe- 
nomena, of  which,  I believe,  there  are  a few  examples. 
But  all  this  is  subordinate  to  the  future  experiments 
which  will  elucidate  the  pilous  structure  more  than  it 
now  is.^’ 

This  structure  exhibits  some  new  peculiarities  which 
we  shall  state. 

The  bulb  of  the  hairs,  or  the  kind  of  canal  from  which 
they  derive  their  origin,  is  in  fact  a small  sac  lodged  in 
the  substance  of  the  skin  or  in  the  sub-cutaneous  cellular 
texture,  and  receiving  the  extremity  of  the  hair  which 
is  implanted  in  it.  This  bulb  is  not  very  evident  in  man. 


292 


ADDITIONS  TO  THE 


but  has  been  described  by  Chii’ac  and  Gaultier,  from  its 
arrangement  in  the  hairs  of  the  whiskers  of  some  animals, 
its  size  in  them  rendering  its  structure  more  evident.  It 
appears  to  contain  like  the  sebaceous  follicles,  the  same 
parts  as  the  skin,  and  to  be  continued  in  the  same  way 
with  this  membrane.  A layer  analogous  to  the  dermis 
is  the  base  of  it,  and  is  evidently  continued  with  the 
dermis  of  the  skin.  Within  this  layer  there  is  an  elon- 
gation of  the  mucous  body,  the  continuity  of  which  with 
this  body  is  seen  very  well  in  animals  whose  skin  is 
coloured  ; this  part  is  soft  and  more  easily  perceived  than 
the  skin  ; it  is  composed,  as  in  the  skin,  of  many  layers. 
The  epidermoid  layer  is  the  inner  one  ; it  is  less  distinct 
than  the  others,  but  it  is  found  in  feathers,  which  have 
a great  analogy  with  the  hairs,  and  in  the  quills  of  quad- 
rupeds, which  are  only  hairs  made  very  strong.  A coni- 
cal papilla,  similar  to  the  asperities  of  the  dermis  which 
surmount  the  palm  of  the  hands,  the  sole  of  the  feet,  &c. 
fills  the  bottom  of  this  kind  of  follicle. 

The  bulbs  of  the  hairs  receive  vessels  and  nerves.  The 
nerves  constitute  in  great  part  the  elongations  which  go 
to  their  external  face,  and  which  occupy  particularly  their 
extremity  opposite  to  the  skin,  they  form  for  them  a sort 
of  pedicle.  Many  anatomists  have  traced  these  nerves 
in  animals  ; in  man  even  nervous  filaments  are  seen  to 
penetrate  the  bulbs  of  the  eyelashes  and  those  of  the 
hairs  situated  at  the  opening  of  the  nostrils.  The  vessels 
are  also  situated,  according  to  some,  in  the  substance  of 
the  elongations  attached  to  the  bottom  of  the  bulbs;  but 
M.  Gaultier  has  seen  them  entering  at  the  other  extremity, 
coming  from  the  dermis  of  the  skin,  and  enclosed  between 
the  dermoid  layer  of  the  bulb  and  the  mucous  layer. 

The  neck  of  these  small  sacs  is  surrounded  with  seba- 
ceous follicles,  pouring  out  an  oily  matter,  w'hich  covers 


PILOUS  SYSTEM. 


S93 


the  surface  of  the  hairs,  and  the  use  of  which  is  to  render 
them  less  brittle.  M.  Gaultier  thinks  that  there  are  nine 
of  these  follicles,  which  are  very  small. 

The  body  of  the  hair  embraces  by  its  root  tbe  papilla  of 
the  bulb  from  which  it  arises  ; it  is  joined  to  the  papilla 
in  this  place,  nearly  in  the  same  way  as  horns  and  feath- 
ers are  united  to  the  elongations  which  serve  for  their 
support.  In  the  interior  of  the  bulb,  the  hair  is  covered 
by  a sheath  which  is  furnished  by  the  epidermis,  and 
which  is  evident  in  the  quills  of  quadrupeds,  and  especi- 
ally in  feathers ; this  sheath  is  discontinued  at  the  place 
where  the  hair  traverses  the  skin  to  go  out,  or  at  least  it 
cannot  be  traced  beyond  there,  perhaps  because  it  is 
broken  off  even  with  the  integuments. 

The  structure  of  the  hair  itself  is  a point  that  is  not 
yet  well  understood.  This  part  seems  to  be,  like  the 
feathers,  horns,  scales,  &c.  a production  of  the  horny 
layer  of  the  skin ; but  it  is  difficult  to  ascertain  the  in- 
ternal arrangement  of  the  substance  which  composes  it. 
The  bristles  of  the  wild  boar  are  formed  by  twenty  fila- 
ments leaving  in  their  interstices  one  or  two  canals  which 
contain  a peculiar  marrow.  On  the  contrary  the  hairs  of 
the  elk,  hedge  hog,  &c.  have  no  filaments;  they  are  con- 
stituted by  a horny  tube,  filled  with  a spongy  and  coloured 
substance.  Hence  there  are  two  different  opinions  in 
relation  to  the  structure  of  the  hairs  in  man.  Some  pre- 
tend that  they  are  filaments  in  juxta-position  ; according 
to  others,  their  arrangement  is  that  of  a tube.  Both  of 
these  opinions  seem  to  be  equally  well  founded  ; 1st,  on 
the  one  hand,  by  examining  against  the  light  a black  hair, 
the  edges  of  it  are  whitish  and  transparent,  which  seems 
to  show  that  the  exterior  of  the  hair  is  of  a different 
nature  from  that  of  the  interior,  but  which  may  be  also 
owing  to  this,  that  the  edge  being  thinner,  the  colour 


294 


ADDITIONS  TO  THE 


must  be  less  evident  in  it ; 2d,  on  the  other  hand,  the 
hairs  in  man  can  be  divided  into  many  filaments,  which 
either  depends  upon  their  structure,  or  the  division  is 
purely  mechanical.  On  the  whole,  the  minuteness  of  the 
objects  prevents  us  from  deciding  on  this  subject.  Onl}'- 
it  is  certain  that  there  is  a colouring  matter  in  the  hair, 
and  that  this  matter  occupies  the  interior  of  it.  The 
hair  is  dyed  with  such  substances  as  the  preparations  of 
lead  which  only  colour  it  by  the  chemical  action  they 
exert  upon  this  matter.  But  it  is  not  known  whether  it 
undergoes  a sort  of  circulation  in  the  hairs,  or  if  when 
once  deposited,  it  is  wholly  beyond  every  motion  of  the 
fluids.  This  matter  is  secreted  with  the  hair  itself  within 
its  horny  substance. 

From  all  that  precedes,  it  is  evident  that  the  two  ele- 
ments of  the  hair,  the  bulb  and  the  body  or  the  hair 
properly  so  called,  have  nothing  in  common  in  their 
structure,  and  consequently  in  their  properties  ; that  the 
hairj  properly  so  called,  is  almost  inorganic,  like  the 
epidermis  and  the  nails,  whilst  its  bulb  on  the  contrary 
enjoys  a very  considerable  degree  of  vitality.  Hence 
why  the  hairs,  though  insensible  themselves,  transmit 
such  painful  impressions  when  they  are  pulled  ; why 
they  are  so  useful  in  animals  with  whiskers,  as  organs  of 
feeling,  the  least  jar  which  agitates  their  extremity  being- 
felt  in  an  instant  ; why,  in  diseases,  the  hairs  are  influ- 
enced by  various  organs,  the  functions  of  their  bulbs  being 
deranged  by  their  connexion  with  the  other  functions  ; 
and  why  nevertheless  they  remain  most  often  foreign  to 
all  the  disorders  which  take  place  in  the  economy,  and 
do  not  feel  them  for  a length  of  time,  &c.  This  sort  of 
productions  should  be  considered  as  the  result  of  a real 
excretion  of  which  the  bulbs  are  the  seat.  Thus  the 
hairs  grow  onlv  at  their  base,  like  the  nails,  of  which  it 


PILOUS  SYSTEM, 


295 


is  easy  to  be  convinced  by  observing  this  growth  upon 
hairs  artificially  dyed,  or  upon  which  an  indelible  mark 
has  been  made  ; the  distance  of  this  mark  from  the  sur- 
face of  the  skin  increases  only  as  the  hairs  lengthen ; and 
it  is  only  near  this  surface  that  the  colour  of  the  hairs 
which  have  been  dyed  seems  to  disappear,  in  proportion 
as  their  substance  is  developed  anew  there.  The  cele- 
brated Mascagni  has  again  brought  forward,  in  a post- 
humous work,  an  opinion  which  has  been  many  times 
before  thrown  out  upon  the  structure  of  the  epidermoid, 
horny  and  pilous  parts  ; he  regards  them  as  a texture  of 
lymphatic  vessels,  and  he  attributes  the  same  texture  to 
the  enamel  of  the  teeth  and  to  most  of  the  organic  tex- 
tures. But  this  vascular  structure,  which  Hedwig  has 
represented  with  so  much  truth  in  the  epidermis  of  plants, 
does  not  appear  to  exist  in  the  epidermis,  hairs  and  nails 
of  man  and  animals. 


MORBID  ANATOMY  OF  THE  PILOUS  SYSTEM. 

Preternatural  whiteness  is  the  most  common  alteration 
of  the  hairs.  Much  has  been  said  of  the  hairs  having 
become  suddenly  white,  and  over  the  whole  extent  of  the 
cranium  at  the  same  time  ; Bichat  has  even  cited  exam- 
ples of  this  fact.  But  have  these  cases  been  sufficiently 
observed  ? They  should  be  doubted,  I think,  especially 
as  no  one  of  them  has  been  related  with  the  necessary 
details,  until  new  observations  confirm  or  destroy  them. 
If  the  facts  are  correct,  they  would  tend  to  prove  that 
there  is  circulation  in  the  hair.  Those  that  are  well 


29a 


ADDITIONS  TO  THE 


known  only  prove  that  an  appearance  of  sudden  dis- 
colouration may  take  place,  when  the  hairs  fall  out  and 
are  replaced  by  others  of  a different  colour.  This  is  what 
is  often  seen  in  phthisical  subjects  who  have  intervals  of 
almost  perfect  health  ; it  then  happens  that  their  hair, 
which  had  become  white  during  the  paroxysm,  falls  out 
and  is  replaced  by  black,  which  it  was  before ; Dr. 
Chaumeton  exhibited  this  phenomenon  a short  time  be- 
fore his  death.  This  may  be  repeated  many  times  suc- 
cessively, and  the  hairs  may  be  thus  alternately  coloured 
and  colourless  according  to  the  general  state  of  the  in- 
dividual. In  ordinary  cases,  the  change  of  colour  does 
not  take  place  in  all  the  hairs  at  once,  but  successively 
in  each  of  them  ; it  begins  at  the  root  and  gains  little 
by  little,  in  proportion  as  this  is  extended  and  the  end 
worn  by  the  action  of  foreign  bodies  ; this  is  easily  ex- 
plained hy  the  change  that  comes  on  in  the  secretion  that 
is  made  in  the  bulbs. 

Alopecia  (or  the  falling  out  of  the  hairs)  is  accompanied, 
under  some  circumstances  and  not  under  others,  by  a sort 
of  atrophy  of  their  bulbs.  This  lesion  is  sometimes  the 
consequence  of  a long-continued  irritation,  as  in  tinea  ; 
at  other  times,  though  rarely  at  the  present  day,  it  is 
owing  to  syphilis  ; but  an  infinity  of  other  causes  may 
also  produce  it.  The  state  of  the  bulbs  in  these  different 
eases  has  not  been  examined. 

The  plica  is  an  affection  also,  the  nature  of  which  is 
but  little  known.  The  best  observers  are  not  agreed  as 
to  what  takes  place  in  this  disease  ; according  to  some, 
the  hairs  acquire  sensibility,  and  are  penetrated  with 
vessels  ; others  assert  that  they  are  only  matted  together. 
It  would  be  possible  to  reconcile  these  two  opinions  by 
admitting  that  the  hairs  become  merely  vascular  at  their 
base,  by  an  extraordinary  growth  of  the  papilla  contained 


PILOUS  SYSTEM. 


297 


in  their  bulbs,  a growth  which  would  raise  this  papilla 
above  the  level  of  the  external  face  of  the  skin,  and 
whose  primitive  irritation  having  caused  the  disease,  or 
that  secondary  one  resulting  from  want  of  cleanliness, 
pulling  the  roots  of  the  hairs,  &c.  would  easil}^  explain 
it.  The  plica  would  then  produce  a phenomenon  analo- 
gous to  what  is  observed  in  feathers,  in  young  birds ; if 
the  papillae  of  their  feathers  exceed  the  level  of  the  integu- 
ments, they  bleed  when  they  are  cut. 

Preternatural  hairs  are  met  with,  besides  under  the  cir- 
cumstances noticed  (Vol.  3d,)  on  the  surface  of  the  skin, 
and  in  consequence  of  the  inflammation  of  this  membrane; 
M.  Boyer  mentioned  in  his  lectures  the  case  of  a woman 
whose  thigh  was  covered  witli  long,  rough  hairs,  after 
erysipelas.  Among  the  cysts  which  contain  hair,  should 
be  noted  those  situated  in  the  superior  eyelid,  near  the 
eyebrow  ; their  hairs  resemble  completely  those  of  the 
e5^ebrow,  and  appear  to  be  only  some  of  them  which 
have  deviated  from  their  usual  direction.  The  hairs  con- 
tained in  the  cysts  of  the  ovarium  are  delicate,  silky, 
light  coloured,  usually  free  from  all  adhesion  and  some- 
times swelled  at  one  of  their  extremities.  It  is  extreme- 
ly rare  that  hairs  arise  in  cysts  formed  in  other  parts. 
Hairs  are  sometimes  found  in  the  meconium  of  new  born 
infants  ; their  origin  is  but  little  known  ; it  is  supposed 
that  they  existed  originally  on  the  skin  of  the  foetus. 


38 


PRETERXATUilAL  TEXTURES. 


IT  remains  for  us,  in  order  to  complete  the  summary 
notice  of  the  principal  changes  which  the  organic  tex- 
ture undergoes  in  diseases,  to  speak  of  the  degenerations 
common  to  all  the  systems  previously  studied,  and  which, 
not  belonging  in  their  nature  to  any  single  one  of  them, 
could  not  be  examined  in  their  particular  history.  The 
description  of  these  degenerations  will  be  at  the  same  time 
a sort  of  completion  of  the  General  Anatomy,  the  different 
simple  textures  of  which  have  embraced,  in  addition  to 
the  natural  organs  of  the  economy,  only  the  preternatural 
productions  which  are  analogous  to  these  organs.  In  fact, 
the  degenerations,  though  always  resulting  from  a species 
of  transformation  or  degeneration  which  affects  the  natural 
textures  in  consequence  of  the  morbid  phenomena  of 
which  these  textures  are  the  seat,  are  really,  when  once 
formed,  independent  to  a cerliiin  extent,  of  these  textures, 
have  in  the  midst  of  them  their  peculiar  life,  seem  as  it 
were  to  be  new  organs  superadded  to  all  the  others,  so 
unlike  are  they  to  those  which  have  given  them  birth, 
and  are  entitled  from  their  structure  and  peculiar  proper- 
ties to  form  a distinct  class,  or  if  it  be  preferred,  a system, 
under  the  name  of  m.orhid  or  preternatural  textures. 


300 


P RET  ER  N Al'  URAL  T EXl’UR  E5'. 


These  textures,  considered  in  this  point  of  view,  pre- 
sent a certain  number  of  common  characters,  which  at 
tlie  same  time  mark  the  difference  between  them  and  the 
natural  textures  of  the  economy.  1st.  Their  structure  is 
in  general  homogeneous,  and  though  they  seem  to  contain 
various  organized  elements,  as  vessels  and  cellular  tex- 
ture, those  fibres  and  laminae  which  characterize  most  of 
the  organic  textures  are  not  seen  in  them.  2d.  They 
have  not,  like  tlicm,  a uniform  organization;  their  most 
important  properties,  such  as  colour  and  consistence, 
change  in  their  different  periods  ; in  general  hard  and 
firm  in  the  beginning,  they  soften  and  become  fluid  even 
in  part,  at  a more  advanced  period,  which  is  precisely 
the  reverse  of  the  other  textures.  3d.  Far  from  being 
able  to  perform  uses  in  harmony  with  the  other  functions, 
as  is  sometimes  done  by  the  natural  textures  when  pre- 
ternaturally  developed  where  they  ought  not  to  exist, 
their  presence  always  produces  more  or  less  remarkable 
derangements  in  the  action  of  the  organs  ; emaciation, 
slow  fever  and  death  are  often  the  consequences  of  them. 
4th.  They  have  not  a permanent  existence  in  the  econo- 
my, but  have  uniformly  a tendency  to  be  destroyed  at  a 
certain  period  ; sometimes,  it  is  true,  this  period  is  late, 
and  they  remain  for  a long  time  in  the  same  state,  making 
a part  of  the  organization,  like  the  natural  textures,  it  is 
especially  at  the  period  of  their  destruction  that  they 
affect  the  health.  5th.  The  diseases  which  affect  them 
have  a peculiar  progress  and  effect  ; thus  inflammation 
uniformly  produces  in  them  the  greatest  derangements 
and  a rapid  destruction,  which  are  propagated  to  the  sur- 
rounding parts. 

Tlie  difl'erent  preternatural  textures  may  be  met  with 
in  almost  all  the  organs  ; but  there  arc  some  which  they 
more  particularly  affect ; often  in  the  same  subject,  they 


PRETERNATURAL  TEXTURES. 


301 


are  found  distributed  at  the  same  time  upon  a great  num- 
ber of  points.  These  textures  frequently  increase  the 
size  of  the  parts  which  they  occupy,  and  form  tumours 
prominent  on  the  exterior.  Their  apparent  situation,  in 
relation  to  tJie  organs,  presents  in  general,  two  varieties  ; 
in  one,  they  seem  to  be  interposed  between  the  textures 
which  compose  these  organs ; in  the  other,  these  textures 
disappear,  and  are  replaced  by  the  preternatural  pro- 
duction. 

How  are  these  textures  produced  in  the  animal  econ- 
omy ? Bayle  and  Laennec  attribute  their  development 
to  a particular'  disposition  of  an  unknown  nature,  which 
exists  in  certain  individuals,  and  regard  the  external 
causes  which  are  commonly  assigned,  at  most  as  only 
occasional  circumstances,  which  favour  the  action  of  this 
occult  cause.  Broussais,  on  the  contrary,  assigns  to  these 
causes  the  principle  part ; according  to  him,  these  pro- 
ductions are  uniformly  a result  of  inflammation,  and  take 
place  when,  in  this,  the  white  vessels  and  the  lymph 
which  they  contain  are  especially  affected,  the  irritation 
not  being  sufficient  to  bring  the  red  part  of  the  blood ; 
the  albumen  variously  combined  with  the  textures,  is  the 
basis  of  these  productions.  J.  F.  Meckel  calls  the  prox- 
imate cause  of  this  kind  of  alterations,  and  generally  all 
the  alterations  of  texture,  an  abherration  of  the  process 
of  growth  ; he  explains  all  these  lesions  in  the  same  way, 
as  J.  Hunter  and  Abernethy  do,  by  the  effusion  of  a fluid 
albuminous  matter,  taking  various  forms  and  requiring  a 
peculiar  and  imperfect  mode  of  organization.  Others 
consider  them  as  productions  analogous  to  the  cryptoga- 
mous  vegetables,  and  which  are  nourished  and  grow 
either  by  imbibition,  or  by  a real  vascular  circulation. 
Disregarding  these  theories,  which  are  more  or  less  well 
founded,  we  shall  treat  only  of  the  anatomical  characters 


302 


PRETERNATURAL  TEXTURES. 


of  the  preternatural  textures ; whatever  may  be  the 
origin  of  these  textures,  it  is  important  to  know  them. 

But  they  exhibit  in  this  respect  many  differences, 
which  are  not  however  striking,  but  are  confounded  with 
each  other  by  insensible  shades  ; besides,  the  parts  in 
which  they  are  situated,  though  not  absolutely  having  ail 
influence  upon  their  nature,  make  them  however  vary  a 
little,  so  that  the  study  of  them  becomes  very  difficult; 
thus  authors  are  not  agreed  in  the  classifications  which 
have  been  given  of  them.  Some  have  made  many  tex- 
tures of  the  same  production  examined  at  different  periods 
of  its  development;  we  have  already  noticed  this  source 
of  error.  Another,  not  less  real,  is  that  oftentimes  many 
of  these  alterations  are  united  together,  whether  they  form 
different  distinct  parts  of  one  texture,  or  whether  they  are 
intimately  intermixed  in  this  texture.  This  union  may 
take  place  not  only  between  morbid  textures  properly 
so  called,  but  also  between  these  and  the  preternatural 
textures  to  which  there  are  analogous  ones  in  the  econ- 
omy; the  osseous  and  fibrous  productions,  for  example, 
are  often  joined  to  the  first,  as  is  seen  especially  in  the 
ovarium,  the  thyroid  gland,  &c.  Hence  it  follows  that 
all  these  textures  are  far  from  being  equally  well  known ; 
that  daily  observation  shows  productions  which  do  not 
resemble  any  of  those  hitherto  described  ; and  finally 
that  there  are  very  common  alterations,  as  the  polypi  of 
the  mucous  membranes,  fungi  of  the  dura-mater,  &c. 
that  we  know  not  where  to  class,  and  which  appear  to 
consist  sometimes  in  a simple  hypertrophy,  and  some- 
times in  a real  degeneration.  The  only  preternatural 
textures  which  have  characters  at  all  striking  are,  1st,. 
Tubercles;  2d,  Scirrhus  ; 3d,  Cancer;  4th,  Melanosis. 
We  shall  now  examine  them  in  succession. 


PRETERNATURAL  TEXTURES. 


303 


I.  Of  Tubercles. 

Tubercles,  or  scrophulous  tubercles,  so  called  from 
their  form  which  is  commonly  round  and  from  their 
most  frequent  cause,  exist  under  many  forms,  which  are 
so  many  degrees  of  this  degeneration,  and  which  may  be 
all  included  in  two  periods,  the  one  of  crudity  in  which 
they  are  in  a solid  state  and  the  other  of  softening.  M. 
Broussais  considers  this  last  as  a true  mode  of  suppuration 
peculiar  to  this  texture,  and  resulting,  like  ordinary  sup- 
puration, from  the  inflammation  which  is  developed  there. 

First  Period.  Greyish  granulations,  semi-transparent, 
quite  firm,  from  the  size  of  a grain  of  millet  to  a grain  of 
hemp  and  irregularly  distributed,  usually  constitute  tuber- 
cles in  the  beginning.  Bayle,  who  observed  them  in  the 
Jungs  in  this  state,  thought  that  it  was  an  alteration  dif- 
ferent from  tubercles ; M.  Laennec  has  proved  that  it  is 
not  so.  These  grains,  as  they  become  larger,  assume 
another  aspect ; they  often  unite  together,  and  form  more 
or  less  considerable  masses  ; they  always  become  opake 
and  yellowish,  at  first  in  their  centre,  and  then  on  the 
circumference,  nearly  in  the  same  way  as  cartilages  which 
are  ossified,  and  acquire  at  the  same  time  the  consistence 
of  hard  cheese.  This  state,  which  is  properly  that  of  the 
crude  tubercle,  is  not  always  distinctly  preceded  by  the 
first,  in  which  the  tubercle  is  called  miliary ; there 
sometimes  takes  place  in  the  beginning  a sort  of  infiltra- 
tion or  impregnation  of  tubercular  matter,  which  suddenly 
invades  a certain  extent  of  the  affected  organ  which  be- 
comes greyish,  more  dense  and  semi-transparent ; yellow 
and  opake  spots  afterwards  appear  in  this  place,  and  the 
second  state  comes  on. 


304 


PRETERNATURAL  TEXTURES. 


The  tubercular  texture  adheres  most  often  to  the  sound 
texture  which  surrounds  it,  it  sometimes  even  seems  to 
be  continued  with  this  texture,  and  at  others,  on  the  con- 
trary, it  is  separated  from  it  with  the  greatest  ease.  In 
some  cases,  a membrane  in  the  form  of  a cyst  surrounds 
the  tubercle ; this  is  especially  when  the  tubercle  is 
developed  slowly.  This  membrane  is  not  always  of  the 
same  nature ; sometimes  soft,  and  as  it  were,  like  the 
integuments  of  pork,  sometimes  more  consistent,  it  some- 
times becomes  cartilaginous  and  even  osseous  ; it  appears 
to  be  the  result  of  an  exudation. 

The  vessels  are  separated  or  obliterated  by  the  tuber- 
cular substance  ; they  are  not  visible  in  the  masses  which 
it  forms. 

Second  Period.  The  tubercles  soften  and  melt  as  it  were 
from  the  centre  to  the  circumference  ; they  are  converted 
sometimes  into  an  opake,  thick,  yellowish  matter,  which 
very  much  resembles  cream,  sometimes  into  a clear  and 
transparent  fluid,  in  which  flakes  similar  to  cheesy  matter 
are  seen  to  swim.  The  evacuation  of  these  products  has 
taken  place,  as  in  abscesses,  sometimes  externally  and  some- 
times internally  ; the  centre  of  the  disease,  which  is 
usually  lined  by  a membrane  of  new  formation,  analogous 
to  the  cyst  of  which  we  have  spoken  above,  cicatrizes,  or 
continues,  open,  and  brings  on  suppuration  and  ulceration 
of  the  texture,  which  forms  the  parietes  of  it,  or  finally 
remains  always,  but  is  clothed  with  a dry,  semi-cartila- 
ginous  membrane,  as  was  first  observed  by  M.  Laennec. 

II.  Of  Scirrhus. 

The  scirrhus  texture  is  firmer  than  the  preceding  ; its 
consistence  varies  from  that  of  the  cartilages  to  the  soft- 
ness of  the  inter-vertebral  fibro-cartilages  ; it  makes  a 


PRETERNATURAL  TEXTURES. 


305 


noise  under  the  scalpel.  Its  colour  is  white,  slightly 
blueish  ; cut  in  thin  slices,  it  appears  semi-transparent. 
It  forms  more  irregular  masses  than  the  tubercular  tex- 
ture ; it  softens  in  the  same  way,  and  is  then  changed  to 
a transparent,  greyish  or  reddish  matter  when  a little 
blood  colours  it,  exhibiting  the  appearance  of  a jelly  or 
syrup. 

The  pancreatoid,  mammary,  (analogous  to  the  texture 
of  the  mamma,)  and  tubercular  sarcomas  of  Abernethy 
should  be  considered  as  varieties  of  scirrhous.  In  the  last 
of  these  three,  the  name  of  which  is  improper,  since  it  is 
agreed  to  give  the  name  of  tubercles  a particular  kind  of 
texture,  and  not  a variety  of  form,  the  scirrhous  mass  is 
divided  into  distinct  lobes. 


m.  Of  Cancer. 

In  pathology,  various  alterations  have  been  designated 
under  this  name,  among  which  scirrhous,  which  we  have 
just  examined,  has  often  been  comprehended.  We  shall 
understand  only  by  cancerous  texture  what  some  have 
called  soft  cancer  ; it  is  the  cerehriform  or  encephaloid 
matter  of  M.  Laennec,  the  fungous  inflammation  of 
Burns,  the  fungous  hematodes  of  Hey  and  Wardrop,  the 
medullary  sarcoma  of  Abernethy,  &c. 

This  texture  has  less  consistence  than  the  scirrhous, 
though  it  has  more  than  the  cerebral  substance  ; it  is  of  a 
milky  white,  variegated,  when  it  is  cut,  by  red  points 
formed  by  the  divided  vessels  ; these  are  in  fact  very 
numerous  in  it  ; but  their  parietes  are  very  thin,  and 
hardl}'^  bear  the  effort  necessary  for  injection.  The  masses 
which  this  texture  forms  are  divided  on  their  surface  by 
lobes  convoluted  nearly  like  those  of  the  brain  ; a very 
39 


306 


PRETERNATURAL  TEXTURES. 


soft  cellular  texture  fills  the  interstices  of  these  lobes. 
These  masses  occupy  at  first  but  a very  limited  extent, 
and  are  afterwards  propagated  in  all  directions  ; this  is 
what  is  seen,  for  example,  in  the  eye,  which  is  frequently 
the  seat  of  this  alteration,  and  in  which  it  occupies  most 
often  in  the  beginning,  a single  point  only  of  the  retina, 
from  which  it  extends  to  the  whole  of  the  eye. 

In  the  period  of  softening,  which  comes  on  soon  in 
this  texture,  and  the  progress  of  which  is  very  rapid,  it 
assumes  the  appearance  of  the  softened  cerebral  substance, 
and  forms  a sort  of  rose-coloured  jelly,  on  account  of  the 
blood  which  is  mixed  with  it ; often  even  the  rupture  of 
the  vessels  which  pass  through  it,  occasions  real  hemor- 
rhages, and  effusions  of  blood  having  some  analogy  with 
those  which  the  same  cause  produces  in  the  brain  ; there 
is  sometimes  formed,  in  consequence  of  these  exudations, 
a membrane  in  the  form  of  a cyst,  as  in  apoplexies. 

Besides,  the  resemblance  is  not  perfect  between  the 
cancerous  texture  and  that  of  the  brain,  and  we  ought  not 
yet  to  admit  the  opinion  of  those  who  regard  these  tex- 
tures as  identical,  and  conclude  from  it  that  there  is  an 
effusion  of  nervous  fluid  in  the  production  of  the  first. 

IV.  Of  Melanosis. 

This  production,  thus  named  by  M.  Laennec,  is  united 
to  the  preceding  by  J.  F.  Meckel.  M.  Broussais  thinks 
that  it  is  a tubercular  texture,  the  black  colour  of  which 
is  owing  to  the  advanced  age  of  the  individuals  who  are 
the  subjects  of  it ; but  it  is  not  proved  that  old  people 
are  the  most  frequently  affected  with  it.  The  same  author 
makes  a more  accurate  approximation  perhaps,  between 
this  colour  and  that  of  the  membranes  in  which  the  blood 


PRETERNATURAL  TEXTURES. 


307 


has  remained  for  a long  time,  as  in  consequence  of  some 
phlegmasias  of  long  standing. 

Melanosis  should  be  distinguished  from  the  black  mat- 
ter of  the  lungs.  The  latter,  which  is  found  in  most 
subjects  after  the  age  of  from  twelve  to  fifteen  years, 
which  increases  progressively  with  age,  and  which  tinges 
the  bronchial  glands,  the  surface  of  the  lungs  and  the 
interstices  between  the  lobules,  does  not  constitute  a 
^disease. 

The  black  colour  of  this  texture  is  perfect  and  entirely 
fopake  ; its  consistence  is  considerable  ; and  it  resists  ef- 
forts made  to  tear  it.  It  accumulates  sometimes  in  masses 
of  a certain  size  ; at  other  times  it  forms  striie  or  plates, 
more  or  less  extensive.  Its  interior  appears  to  be  homo- 
geneous ; no  kind  of  structure  is  discoverable  in  it.  This 
matter  rarely  becomes  soft ; when  this  does  take  place, 
there  results  from  it  a sort  of  black  pap  or  a serous  fluid, 
mixed  with  a grumous  matter  of  the  same  colour. 

Melanosis  is  much  more  compatible,  than  the  other 
morbid  textures,  with  a state  of  health  ; so  diflerent  is  its 
nature  from  that  of  these  textures.  M.  Barruel,  chief  of 
the  chemical  department  of  the  Faculty  of  Medicine,  has 
recently  examined  for  me  some  melanosis  extracted  from 
a mare,  which  had  a great  quantity  of  it  in  the  muscles, 
in  many  viscera  and  especially  under  the  skin  of  the 
perineum  and  the  mammae  ; it  appears  from  his  exami- 
nation that  melanosis  must  be  considered  as  a mass  of 
matter  coloured  with  blood  and  fibrin,  both  in  a peculiar 
state,  and  in  which  is  found  a little  albumen,  three  dis- 
tinct fatty  substances,  and  much  of  the  phosphate  of  lime 
and  iron. 


- I. 

t 

^vv.VJS:V 

- ■ ' .'"t 

' •'  '•■•  .'V»  ■ ,. 

' ‘ ' . . ' 'llA.4 

• ■ •'  -• 

■'  4,>- , 

\ " ■ •:  r 

.V'!  , 

. .i  ■ niuv:.'  ,.  sf.: 

;>  . %r'  ■■,  % . 


. yi 


.mJiLYTICAL  TABLE  OF  COJTTEJVTS. 


ADDITIONS  TO  THE  GENERAL  OBSERVA- 
TIONS. 


PAGE 

Anatomical  Elements. — Attempts  have  been  made  to  dis- 
cover what  are  the  primitive  elements  of  the  tex- 
tures.— Elementary  fibre  of  the  ancients. — There  are 
three  elements  ; the  cellular,  nervous  and  muscular 
fibre. — The  albugineous  fibre  considered  as  a fourth 

element. Elementary  forms. Their  division. 

Opinion  of  J.  F.  Meckel.  16 

Classification  ofi  Morbid  Anatomy. — Method  followed  by 
the  moderns. — Classification  of  Meckel. — Order  that 
we  shall  adopt.  22 


ADDITIONS  TO  THE  CELLULAR  SYSTEM. 


Adipose  Texture. — Names  which  different  authors  have 
given  to  this  texture. — External  Forms. — Organiza- 
tion.— Blood  Vessels. — Cellular  Texture. — Unknown 
Absorbents  and  Nerves. — The  Adipose  Texture  re- 
sembles the  Cellular. — Characters  which  distinguish 
them.  27 


310 


ANALYTICAL  TABLE 


PAGE 

Chemical  JVature  of  the  Fat. — It  is  formed  of  two  princi- 
ples elaine  and  stearine, — Their  characters. — Means 
of  separating  them. — Their  proportions  var/. — The 
fat  is  fluid  in  the  living  body. — Acids  which  the  fat 
furnishes  when  it  is  treated  with  alkalies.  32 

Intimate  JVature  of  the  Cellular  Texture. — The  ancients 
appear  not  to  have  known  this  texture. — Authors  who 
have  described  it  successively. — Opinion  of  Bordeu 
adopted  by  some  moderns. — Facts  upon  which  they 
are  founded. — It  is  to  be  determined  by  inspection.  33 


MORBID  ANATOMY  OF  THE  CELLULAR 
SYSTEM. 


I.  Alterations  in  the  External  Forms. 

Anasarca. — Fatty  Tumours. — Emphysema. — Hardening 
oftiio  Cellular  Texture. — Elephantiasis.  37 

II.  Alterations  in  the  Organization. 

Phlegmon. — Mode  of  adhesion  of  the  divided  cellular 
texture. — Cicatrization  of  this  texture  laid  bare. — 
Phenomena  that  foreign  bodies  produce  in  it. — Some- 
times these  bodies  remain  without  producing  any  in- 
convenience.— Animated  foreign  bodies. — Osseous  and 
cartilaginous  transformation. — Fibrous,  Serous  and  Mu- 
cous transformations. — Various  degenerations.  38 

III.  Alterations  in  the  Development. 

Preternatural  development. — Membrane  of  the  fleshy 
granulations. — How  it  is  formed.  41 


OF  CONTENTS, 


311 


ADDITIONS  TO  THE  NERVOUS  SYSTEM  OF 
ANIMAL  LIFE. 


PAGE 

j\’'erves  which  the  Brain  furnishes. — The  optic  iiei^e  does 
not  come  from  the  brain,  but  from  the  medulla 
oblongata. — The  origin  of  the  olfactory  is  not  well 
known. — The  olfactory  bulb  -of  animals. — It  is  con- 
tinued with  the  peduncles  of  the  medulla  oblongata. — 

The  puipy  portion  of  the  olfactory  nerves  in  man  is 
analogous  to  it,  according  to  some  anatomists.  43 

Origin  of  the  JVerves. — They  arise  from  the  grey  sub- 
stance.— Arrangement  of  this  substance  in  the  spinal 
marrow. — It  exists  also  at  the  origin  of  the  cerebral 
nerves. — It  should  he  inferred  from  this,  that  it  pro- 
duces the  nervous  substance.  44 

Crossing  of  the  jYerves. — It  takes  place  in  the  medulla 
oblongata. — Consequences  in  relation  to  paralysies.  4& 
Composition  of  the  JVervous  System. — Principles  that  M. 
Vauquelin  has  found  in  it. — Properties  of  the  two  pe- 
culiar fatty  substances. — Proportions  of  these  principles 
in  the  spinal  marrow  and  in  the  nerves.  47 

Texture  peculiar  to  the  JVervous  System. — Two  substances. 

— White  substance. — The  cerebral  substance  is  com- 
posed of  fibres. — Method  of  studying  its  structure. — 
Course  of  those  of  the  fibres  which  come  from  the 

medulla  oblongata. Fibres  of  the  commissures. 

Structure  of  the  cerebellum. — The  substance  of  the 
nerves  has  also  fibres.— This  is  likewise  the  case  with 
that  of  the  spinal  marrow. — Arrangement  of  these  last. 

— Grey  substance. — Its  arrangement. — Its  structure. — 

The  microscope  besides  discovers  globules  in  the 
nervous  texture. — They  resemble  those  of  the  blood. 

— Substance  which  secretes  them. — Arrangement  of 
these  globules. — They  do  not  appear  to  be  the  seat  of 
the  colouring  matter  in  the  grey  substance.  48 

Development  of  the  .Yervous  Centres. — Various  authors  ' 
have  been  engaged  with  the  subject. — The  dimen- 
sions of  the  cerebrum,  cerebellum  and  spinal  marrow 
are  in  an  inverse  proportion  at  the  different  periods  of 


312 


ANALYTICAL  TABLE 


PAGE 

gestation. — Fissure  which  divides  all  these  parts  in 
the  beginning. — The  conformation  of  the  cerebrum, 
at  first  very  simple,  becomes  gradually  complicated. — 
Development  of  the  cerebellum,  the  cerebral  protu- 
berance, and  the  spinal  marrow. — Texture  of  the 
encephalon  at  the  different  periods. — The  white  sub- 
stance appears  before  the  grey. — Exception,  according 
to  M.  Serres,  with  regard  to  the  thalami  nervorum  op- 
ticorum  and  the  corpora  striata. — The  vessels  precede 
both  substances.  53 

Development  of  the  JVei'ves. — Period  at  which  they  appear. 

— It  is  not  the  same  for  all. — Development  of  their  tex- 
ture. 59 


MORBID  ANATOMY  OF  THE  NERVOUS  SYS- 
TEM OF  ANIMAL  LIFE. 


1.  Alterations  in  the  External  Forms. 

Increase  of  size  in  the  nerves. — Diminution. — The  brain 
diminished  in  size. — Softening  of  the  nerves. — Hard- 
ening and  softening  of  the  brain. — Softening  of  the 
spinal  marrow. — Alterations  of  situation  and  form.  60 

II.  Alterations  in  the  Organization. 

Inflammation. — la  the  nerves. — In  the  brain. — Mode  of 
reunion  of  the  nerves. — Nature  of  the  cicatrix. — 
Opinion  of  Arnemann. — What  takes  place  at  the  supe- 
rior end  in  amputations. — Solutions  of  continuity  in 
the  brain  and  the  spinal  marrow. — Osseous,  fibrous 
and  cartilaginous  transformation. — Cysts. — Degenera- 
tions. 62 

III.  Alterations  in  the  Development. 

Defects  of  conformation.- — Partial  and  total  absence. — 
Irregularities  of  forms. — Congenital  affections. — Ana- 
tomical varieties. — No  preternatural  development.  65 


OF  CONTENTS. 


313 


ADDITIONS  TO  THE  NERVOUS  SYSTEM  OP 
ORGANIC  LIFE. 


PACE 

Insulation  of  the  Great  Sympathetic. — Opinions  of  authors 
upon  this  insulation. — Experiments  of  Legallois. — Op- 
posite experiments. — Conclusion  that  must  be  drawn 
from  them.  67 

Structure  of  the  Ganglions. — They  contain  the  two  sub- 
stances pointed  out  by  Scarpa. — Arrangement  of  (be 
nervous  filaments  in  their  interior. — Peculiar  grey 
substance. — It  differs  from  the  cerebral. — It  does  not 
appear  to  be  changed  into  fat  in  fat  subjects,  as  Scarpa 
said.  70 

Uses  of  the  Ganglions. — They  are  of  two  kinds,  accord- 
ing to  physiologists. — Idea  the  most  generally  admit- 
ted. 73 

Ganglions  of  Animals. — The  nervous  system  of  the  lower 
classes  of  animals  has  hardly  any  analogy  with  that  of 
the  superior  animals,  though  many  have  attempted  to 
shew  approximations. — What  is  called  a ganglion  in 
the  former,  does  not  perhaps  deserve  that  name. — 

In  the  vertebral  animals,  the  development  of  the  gan- 
glions varies  according  to  many  circumstances.  75 


ADDITIONS  TO  THE  VASCULAR  SYSTEM 
WITH  RED  BLOOD. 

Situation  of  the  Arteries. — They  are  almost  everywhere 
situated  in  the  direction  of  the  flexion  of  the  articula- 
tions.— Advantages  of  this  arrangement. — They  are  in 
general  on  the  internal  side  of  the  limbs.  77 

Termifiation  of  the  Arteries. — Differences  in  the  length  of 
their  course,  in  their  mode  of  distribution,  their  num- 
ber and  size,  and  in  the  net-works  which  their  divisions 
form. 


40 


78 


314 


ANALYTICAL  TABLE 


PAGE 

Resistance  of  the  Arteries. — Membranes  which  support  the 
effort,  according  to  the  direction  in  which  it  is  made. — 
Causes  which  have  an  influence  upon  this  resistance. 

— Experiments  of  Wintringham  and  Gordon. — Differ- 
ence between  the  convex  and  concave  side  of  the  arte- 
rial curves.  80 

JVature  of  the  Middle  Coat  of  the  Arteries. — Reasons  alleged 
by  those  who  believe  it  muscular. — They  are  not  suf- 
ficient to  make  us  regard  it  as  such. — This  coat  belongs 
to  the  yellow  fibrous  system.  81 

Cellular  Membrane  and  Sheath  of  the  Arteries, — Characters 
of  the  cellular  membrane. — Arrangement  of  the  cellu- 
lar texture  around  it. — What  should  be  understood  by 
the  cellular  sheath  of  the  arteries. — Varieties  which  it 
exhibits. — These  varieties  explain  various  morbid  phe- 
nomena. 82 

Nerves  of  the  Arteries. — The  branches  have  more  of  them 
than  the  trunks. — Mode  of  their  distribution.  84 

Irritability  of  the  Arterial  Texture. — Reasons  assigned 
by  those  who  admit  it. — Experiments  of  Verschuir, 
Bikher,  Vanden-Bos,  Giulio,  Rossi,  Home  and  Thom- 
son.— Other  facts. — Consequences. — The  contraction 
of  the  arteries  is  more  evident  in  the  small  ones.  85 

Actio7i  of  the  Arteries  in  the  circulation. — The  contraction 
of  the  arteries  is  one  of  the  causes  of  the  motion  of 
the  blood.  87 

Development  of  the  Vascular  Sijstejn. — It  is  a point  still 
obscure. — Result  of  the  researches  made  upon  the 
chick. — Consequences.  88 


MORBID  ANATOMY  OF  THE  VASCULAR  SYS- 
TEM ^VITH  RED  BLOOD. 


I.  Alterations  in  the  External  Forms. 

Increase  of  size  of  the  arteries. — Their  growth  in  length. 
— Their  partial  dilatation  (aneurism). — Their  uniform 
dilatation. — Contraction  of  the  arteries. — It  may  extend 


OF  CONTENTS. 


315 


PAGE 

to  obliteration. — Change  in  the  mode  of  distribution  of 
the  arteries,  in  consequence  of  the  obliteration  of  a 
principal  trunk.  90 

II.  Alterations  in  the  Organization. 

Inflammation  of  the  internal  membrane. — Obliteration 
which  results  from  it. — Ivlode  of  adhesion  of  the  arte- 
rial parietes. — Other  terminations  of  this  inflammation. 

— Alterations  peculiar  to  the  surrounding  cellular  tex- 
ture.— Brittleness  from  inflammation  of  the  cellular 

coat. Peculiar  redness  of  the  internal  membrane 

resembling  its  inflammation. — Wounds  of  the  arteries. 

— Results  of  experiments  upon  dogs. — Punctures  heal 
perfectly. — In  the  more  extensive  wounds,  the  termi- 
nation differs  according  as  the  cellular  .sheath  is  un- 
touched or  not. — What  takes  place  in  transverse  divi- 
sions.— The  progress  of  these  wounds  is  a little  differ- 
ent in  man. — Solutions  of  continuity  which  affect  only 
one  part  of  the  membranes. — Experiments. — In  what 
consists  the  internal  mixed  aneurism. — Rupture  of  the 
internal  membranes. — Its  consequences  in  different 
cases. — Foreign  bodies  applied  to  the  arteries. — Ossi- 
fication of  the  arteries. — Cartilaginous  transformation. 

— Fibrous  and  Cellular  transformations. — Degenera- 
tions peculiar  to  the  arterial  texture. — Fungi. — Ex- 
crescences.— Pultaceous  matter. — Common  degenera- 
tions. 92 

III.  Alterations  in  the  Development. 

The  varieties  of  the  arteries  are  numerous. — Some  only 
are  important  in  relation  to  the  circulation. — Preter- 
natural development  of  the  arteries.  102 


ADDITIONS  TO  THE  VASCULAR  SYSTEM 
WITH  BLACK  BLOOD. 

Venom  Valves. — Their  number  in  the  different  parts. — 
Arrangement  of  their  edge. — Dilatation  of  the  vein 
where  they  are  situated. — Their  structure. — Their 
differences.  105 


316 


ANALYTICAL  TABLE 


1>AGE 

Contractility  of  the  Veins. — The  veins  have  a vital  action. 

— Facts  which  prove  it. — Their  mode  of  contraction 
cannot  be  referred  to  any  other.  107 

Venous  Circulation. — Opinion  of  Harvey. — Influence  of 
the  heart  upon  this  circulation.  108 

Development  of  the  V enous  System. — A part  of  this  system 
is  developed  before  the  arterial. — Doubts  in  relation 
to  the  development  of  the  aorta. — Most  of  the  veins 
are  formed  after  the  arteries.  109 


MORBID  ANATOMY  OF  THE  VASCULAR  SYS- 
TEM WITH  BLACK  BLOOD. 

I.  Alterations  in  the  External  Forms. 

Dilatation  of  the  veins. — Their  contraction.  110 

II.  Alterations  in  the  Organization. 

Inflammation. — Cases  in  which  it  is  observed. — Effects 
which  result  from  it. — Disorders  which  it  produces. — 
Adhesive  inflammation. — Venous  ruptures. — Aneuris- 
mal  varix  and  varicose  aneurism. — Osseous  transfor- 
mations.— Concretions  found  in  the  veins.  Ill 

III.  Alterations  in  the  Development. 

Frequency  of  anatomical  varieties  compared  with  that  of 
the  arteries. — Preternatural  development.  114 


KiaEEsesaKma 


ADDITIONS  TO  THE  CAPILLARY  SYSTEM. 

Continuation  of  the  Arteries  with  the  Veins,  Exhalants,  4*c. 

— Various  opinions  of  the  ancients. — Proofs  of  the  con- 
tinuation of  the  arteries  with  the  veins. — The  continu- 
ation with  the  exbalants  and  excretories  is  less  certain.  115 


OF  CONTENTS. 


317 


PAGE 

Erectile  Texture. — This  texture  is  entirely  vascular,  as 
various  anatomists  have  proved. — Phenomena  of  which 
it  is  the  seat. — Organs  which  this  texture  composes.  116 
Capillary  Circulation. — Proofs  that  the  heart  has  an  in- 
fluence upon  it,  119 


MORBID  ANATOMY  OF  THE  CAPILLARY 
SYSTEM. 

I.  Alterations  in  the  External  Forms. 

Preternatural  growth.  120 

II.  Alterations  in  the  Organization. 

Effects  produced  by  contusion  and  concussion. — Wounds.  121 

III.  Alterations  in  the  Development. 

Preternatural  Development. — Its  mechanism. — Preter- 
natural erectile  texture.  121 


ADDITIONS  TO  THE  EXHALANT  SYSTEM. 

Arrangement  of  the  Exhalant  Vessels. — Their  existence  is 
not  proved. — There  are  however  white  vessels. — 
Experiment  of  Bleuland. — We  are  ignorant  of  the  mode 
of  the  termination  of  these  vessels.  125 


ADDITIONS  TO  THE  ABSORBENT  SYSTEM. 

Origin  of  the  Absorbents. — What  is  known  of  this  origin. 

— Observation  of  Cruikshank. — Experiment  of  Mas- 
cagni.— Result  of  injections.  127 

Venous  Absorption. — Termination  of  the  Absorbents. — Dif- 
ferent opinions  respecting  venous  absorption. — Facts 
which  prove  this  absorption.— Consequences. — Obser- 
vation of  Abernethy.  128 


318 


ANALYTICAL  TABLE 


PAGE 

Structure  of  the  Lrjmphatic  Glands. — The  opinion  rejected 
by  Bichat  is  that  of  Mascagni  and  Gordon. — Considera- 
tions in  support  of  this  opinion. — Cellular  texture, 
veins  and  nerves  of  the  lymphatic  glands.  129 

Properties  of  the  .libsorbents. — Sensible  Organic  Contrac- 
tility.— Facts  which  demonstrate  this  property.  131 


MORBID  ANATOMY  OF  THE  ABSORBENT 
SYSTEM. 

I.  Alterations  in  the  External  Forms. 

Dilatation  of  the  absorbent  vessels.  132 

II.  Alterations  in  the  Organization, 

Inflammation. — Wounds. — Spontaneous  ruptures. — Ossifi- 
cation of  the  lymphatic  glands. — Their  tubercular 
affection.  132 

III.  Alterations  in  the  Development. 

Frequency  of  anatomical  varieties. — ^The  thoracic  duct 
exhibits  a great  number  of  them.  133 


ADDITIONS  TO  THE  OSSEOUS  SYSTEM. 

Intimate  Structure  of  the  Bones. — Various  opinions. — Ex- 
amination of  the  facts  in  relation  to  these  opinions. — 


There  appear  to  be  in  the  bones  laminae,  fibres  and 
areolae.  135 

.Arrangemen  t of  the  Pores  of  the  Compact  Texture.  137 

Composition  of  the  Osseous  Texture. — Analysis  of  M.  Berze- 
lius.— Difi'erence  observed  by  other  chemists. — Com- 
position of  the  bones  in  an  anatomical  point  of  view.  ib. 
Feins  of  the  Diploe. — Their  arrangement. — They  exist  in 
different  bones.  139 


OF  CONTENTS. 


319 


Developmeyit  of  the  Osseous  System. — Authors  who  have 
been  particularly  engaged  with  this  subject. — All  the 
bones  are  not  at  first  cartilaginous. — Period  at  which 
the  osseous  state  begins  in  the  different  bones. — 
Changes  which  the  cartilage  that  is  ossified  undergoes. 
— Ossification  examined  in  the  long  and  broad  bones. — 
Mode  of  increase  in  the  length  of  the  long  bones. — 
Increase  in  thickness  in  the  three  species  of  bones. 
— Changes  which  the  cavities  of  the  bones  undergo. — 
Other  changes  which  take  place  in  this  system  in  old 
?ge. 

Second  Dentition  considered  at  the  period  of  cvfthrg. — Error 
that  should  be  corrected  in  all  the  editions  of  the  work 
of  Bichat. 


MORBID  ANATOMY  OF  THE  OSSEOUS 
SYSTEM. 


I.  Alterations  in  the  External  Forms. 

Tumours  of  the  hones. — Increase  of  density  of  the  osse- 
ous texture. — Atrophy  of  this  texture. — Softening. — 
Effect  of  compression  upon  the  bones. — Changes  in  the 
natural  relations  of  the  bones. — False  articulations. 

II.  Alterations  in  the  Organization. 

Suppuration  of  the  bones. — Necrosis. — Reproduction  of 
the  bones  in  this  affection. — Denudation  of  the  bones. 

— Fractures. Mechanism  of  the  formation  of  the 

callus. — What  should  be  thought  of  the  opinions  of 
authors  upon  this  subject. — Fibrous  reunion  of  cer- 
tain fractures. — Various  transformations  and  degene- 
rations. 


III.  Alterations  in  the  Development. 

Defects  of  conformation. — Preternatural  osseous  texture. 


PAGE 


139 

145 


146 

149 

I 

1 55 


320 


ANALYTICAL  TABLE 


ADDITIONS  TO  THE  MEDULLARY  SYSTEM. 

PAGE 


Organization  of  the  Medullary  Membrane. — Experiment 

which  renders  it  more  conspicuous. Vessels  and 

nerves  of  this  membrane. — Adipose  vesicles.  157 

Sensibility  of  the  Medullary  Membrane.  158 

Development.  159 

Functions. — The  marrow  does  not  transude  in  order  to 
produce  the  synovia. — Other  hypothetical  uses  attri- 
buted to  the  marrow. — Its  true  functions  and  those  of 
the  medullary  membrane.  160 


MORBID  ANATOMY  OF  THE  MEDULLARY 
SYSTEM. 

This  system  is  ■no  doubt  altered  in  syphilis. — Changes 
which  it  undergoes  in  various  cases. — Spina  ventosa  is 
a cancer  of  the  medullary  membrane. — Alterations  of 
the  marrow  in  phthisical  patients.  161 


ADDITIONS  TO  THE  CARTILAGINOUS  SYSTEM. 

Peculiar  Texture. — Its  organization  is  not  very  apparent. 

— Various  opinions.  163 

Chemical  Composition. — Results  obtained  by  modern  che- 
mists.— Differences  according  to  age.  165 


MORBID  ANATOMY  OF  THE  CARTILAGINOUS 
SYSTEM. 

I.  Alterations  in  the  External  Forms.  166 

II.  Alterations  in  the  Organization. 

Inflammation  has  not  been  observed  in  the  cartilages. — 
What  takes  place  when  they  are  denuded  or  broken. 


OF  CONTENTS, 


321 


PAGE 

— Reproduction  of  the  cartilages. — Osseous  transfor- 
mation. 167 

III.  Alterations  in  the  Development. 

Defects  of  conformation. — Preternatural  cartilaginous 
textures.  169 


ADDITIONS  TO  THE  FIBROUS  SYSTEM. 

Yellow  Fibrous  Texture. — It  forms  a distinct  class  in  the 
fibrous  system. — It  is  placed  wherever  a continual  re- 
sistance is  required. — Its  differences  from  the  white 
fibrous  texture. — Its  properties. — Its  uses,  171 


MORBID  ANATOMY  OF  TPIE  FIBROUS  SYSTEM. 

I.  Alterations  in  the  External  Forms. 

Thickenings  of  the  ligaments  and  tendons. — Stiffness 
which  they  acquire  under  some  circumstances.  173 

II.  Alterations  in  the  Organization. 

Inflammation. — Mode  of  reunion  of  divided  fibrous  or- 
gans.— Ossification  rare. — Degenerations.  174 

III.  Alterations  in  the  Development. 

P.,elaxation  of  the  ligaments  in  some  defects  of  conforma- 
tion.— Preternatural  fibrous  texture. — Fibrous  body.  175 


ADDITIONS  TO  THE  FIBRO-CARTILAGINOUS 
SYSTEM. 

Of  the  Nature  of  the  Membranous  Fibro-cartilages. — They 
are  true  cartilages.  179 

Of  the  Forms  of  the  Fibro-cartilaginous  System. — They  are 
very  various. — Table  of  this  system. 

41 


180 


322 


ANALYTICAL  TABLE 


MORBID  ANATOMY  OF  THE  FIBRO-CARTI- 
LAGINOUS  SYSTEM. 

PAGE 

I.  Jllterations  in  the  External  Forms.  182 

II.  Alterations  in  the  Organization.  ih. 

III.  Alterations  in  the  Development. — Preternatural  fibro- 

cartilages.  183 


ADDITIONS  TO  THE  MUSCULAR  SYSTEM  OF 
ANIMAL  LIFE. 

Intimate  Structure  of  the  Muscles. — Divisibility  of  the  mus- 
cular fibi’e. — Size  of  this  fibre. — Inequalities  which  it 
exhibits  on  its  surface. — Microscopical  observations. — 

Is  the  muscular  fibre  solid  or  hollow.  185 

Influence  of  the  JVerves  upon  Muscular  Irritability. — What 
takes  place  when  all  the  nerves  of  a muscle  are  cut. — 

— Consequences. Many  physiologists  consider  the 

nerves  only  as  conductors. — It  is  difficult  to  resolve 
the  question  in  an  absolute  manner.  187 

Quickness  of  the  Muscular  Contractions. — Measure  of  this 
quickness. — Method  of  Dr.  Wollaston  for  estimating  it.  190 
Size  of  the  Muscles  in  Contraction. — Causes  of  error  in  the 
experiments  made  to  determine  it. — Observation  of 
Erman.  191 

State  of  the  Circulation  in  the  Muscles  in  Contraction. — It  is 
more  rapid  according  to  some  physiologists. — Exami- 
nation of  the  facts  upon  which  they  are  founded. — 

This  opinion  is  by  no  means  demonstrated.  192 

State  of  the  Muscles  after  Death. — Stiffness  in  the  dead  body. 

— Its  causes. — Varieties. — Seat.  194 


ADDITIONS  TO  THE  MUSCULAR  SYSTEM  OF 
ORGANIC  LIFE. 

Infuence  of  the  JVervous  System  upon  the  Muscles  of  Organic 
l,ife, — it  is^difficult  to  determine  it. — Influence  of  the 


OF  CONTENTS. 


323 


PAGE 

brain  upon  the  contraction  of  these  muscles. — Influ- 
ence of  the  spinal  marrow  and  the  nerves.  197 

Duration  of  the  Organic  Contractility. — It  varies  in  different 
muscles. Order  in  which  this  property  is  extin- 
guished. 200 

Force  of  Dilatation  of  the  Mascles.—Maay  facts  have  been 
incorrectly  referred  to  this  force. — Its  existence  is 
doubtful.  ' 201 


MORBID  ANATOMY  OF  THE  MUSCULAR 
SYSTEM. 

I.  Alterations  in  the  External  Forms. 

Hypertrophy  and  atrophy. — The  pretended  fatty  degene- 
ration belongs  to  this  last. — Softening  of  the  muscles. 

— Effect  of  their  elongation. — Their  shortening  and 
displacement.  204 

II.  Alterations  in  the  Organization. 

Inflammation. — Wounds. — Transformations.  205 

III.  Alterations  in  the  Development. 

Defects  of  conformation. — Preternatural  muscular  tex- 
ture. 206 


ADDITIONS  TO  THE  MUCOUS  SYSTEM. 

Villi  of  the  Mucous  Membranes. — Forms  of  these  villi  seen 
through  a microscope. — Various  opinions  upon  their 
structure. — Upon  the  termination  of  the  lymphatic 
vessels  on  their  summit. — The  existence  of  nerves  in 
these  villi  is  not  demonstrated. — Their  blood  vessels 
and  lymphatics  are  evident.  209 

Mucous  Glands. — They  are  follicles  and  not  properly 
glands. — Their  arrangement. — There  are  simple  and 
compound  ones. — Arrangement  of  these  last. — Peculiar 
depressions  of  the  mucous  membranes. — Classification 
of  the  follicles  by  Horae. — Follicular  secretion.  212 


324 


ANALYTICAL  TABLE 


PAGE 

Development  of  the  Mucous  System. — It  is  continuous,  in 
the  first  period  of  conception,  with  the  membranes  of 
the  ovum. — Development  of  the  intestine  in  the  chick. 

— Applications  to  man. — Other  ideas  on  this  subject.  216 


MORBID  ANATOMY  OF  THE  MUCOUS  SYSTEM. 

I.  Alterations  in  the  External  Forms. 

Dilatation  and  contraction  of  the  mucous  ducts. — Adhe- 
sions.— Hypertrophy  of  the  mucous  membranes. — De- 
fects of  situation  and  form.  220 

II.  Alterations  in  the  Organization. 

Inflammation. — False  membranes. — Cicatrices  of  the  mu- 
cous membranes. — Transformations. — Cancer.  222 

III.  Alterations  in  the  Development. 

Their  two  kinds  are  distributed  unequally  in  the  different 
systems. — Defects  of  conformation  in  the  mucous  sys- 
tem.— Preternatural  mucous  membranes.  223 


ADDITIONS  TO  THE  SEROUS  SYSTEM. 

I.  Alterations  in  the  External  Forms. 

Increase  of  nutrition. — It  becomes  thinner  and  is  dis- 
placed. 227 

II.  Alterations  in  the  Organization. 

Alterations  of  the  serous  fluids  in  consequence  of  inflam- 
mation.— They  explain  most  of  the  changes  which 
this  affection  produces  in  the  serous  membranes. — 
Reproduction  of  the  serous  texture.— Ossification. — 
Various  degenerations.  229 

III.  Alterations  in  the  Development. 

Defects  of  conformation. — Preternatural  serous  mem- 
branes.— Cysts. — Mode  of  production  of  cysts. — Their 
organization. — Substances  which  they  contain. — How 
they  are  distinguished  from  hydatids.  232 


OF  CONTENTS. 


325 


ADDITIONS  TO  THE  SYNOVIAL  SYSTEM. 

PAGE 

Conformation  of  the  Synovial  Membranes. — Proofs  that 
thej  form  sacs  without  an  opening.  236 

Synovial  Fringes. — Their  nature  and  arrangement. — All 
the  synovial  membranes  have  them. — Their  differ- 
ences, situation  and  uses. — Analogous  fringes  in  the 
mucous  system.  239 

Parallel  between  the  Synovial  Membranes  and  the  Serous  Ones. 

— There  are  fewer  vessels  in  the  synovial  membranes, 

— The  structure  of  these  is  more  distinctly  fibrous. — 
They  seem  to  be  less  extensible.  241 

Existence,  Forms  and  Organization  of  the  Synovial  System  of 
the  Tendons. — This  system  is  gradually  confounded  with 
the  cellular. — Circumstances  which  have  an  influence 
upon  the  number  of  the  tendinous  synovial  membranes. 

— Manner  of  observing  these  membranes. — Differences 
in  their  forms,  structure,  fluid  and  properties.  242 


MORBID  ANATOMY  OF  THE  SYNOVIAL 
SYSTEM. 

I.  Alterations  in  the  External  Forms. 

Dropsy. — Adhesions.  245 

II.  Alterations  in  the  Organization. 

Different  effects  of  inflammation. — Foreign  bodies  in  the 
articulations. — They  exist  originally  without  the  syno- 
vial membrane. — Their  different  states. — Impressions 
which  they  sometimes  produce. — Peculiar  bodies  found 
in  the  bursas  mucosas. — Alterations  of  the  synovial 
membranes  in  white  swellings.  246 

III.  Alterations  in  the  Development. 

Preternatural  synovial  membranes.  248 


326 


ANALYTICAL  TABLE 


ADDITIONS  TO  THE  GLANDULAR  SYSTEM. 

PAGE 

Intimate  Structure  of  the  Glands. — The  opposite  results  ob- 
tained by  Rujsh  and  Malpighi  are  owing  perhaps  only 
to  the  diversity  of  the  texture  of  the  glands.  249 

Influence  of  the  Nerves  upon  the  Action  of  the  Glands. — This 
action  is  in  general  but  little  known. — Difficulty  of 
ascertaining  the  influence  of  the  nerves. — Experi- 
ments which  render  it  doubtful.  2bl 


MORBID  ANATOMY  OF  THE  GLANDULAR 
SYSTEM. 

I.  Alterations  in  the  External  Forms. 

Hypertrophy  and  atrophy. — Changes  of  colour,  consist- 
ence and  situation.  253 

II.  Alterations  in  the  Organization. 

Inflammation, — W oUnds. — Transformations.  254 

III.  Alterations  in  the  Development. 

Anatomical  varieties.  255 


ADDITIONS  TO  THE  DERMOID  SYSTEM. 

Colouring  Matter. — Mucous  Body. — Papillai. Layers  of 

the  mucous  body. — This  body  is  not  admitted  by  all 

anatomists. Experiments  in  order  to  obtain  the 

colouring  matter. — Its  mode  of  production. — It  is  in 
circulation  in  the  skin. — Examination  of  the  other 
parts  of  the  mucous  body. — Sanguineous  bunches  and 


papillae. — Their  arrangement  and  structure.  257 

Cutaneous  Absorption. — Absorption  by  contact  is  not  de- 
monstrated.— Gaseous  absorption.  263 

Sebaceous  Glands. — Proofs  of  their  existence. — -Their 
structure.  266 


OF  CONTENTS, 


327 


MORBID  ANATOMY  OF  THE  DERMOID 
SYSTEM. 


PAGE 

, I.  Alterations  in  the  External  Forms. 

Changes  which  the  skin  when  distended  undergoes. — 
Preternatural  growth  of  the  different  parts  of  the  skin. 

— Horny  productions. — Increase  of  (he  sebaceous  fol- 
licles.— Tumours  which  result  from  it. — Cutaneous 
atrophy. — Bunches  on  the  skin  and  thickening  of  it.  268 

II.  Alterations  in  the  Organization. 

Effects  produced  by  inflammation. — Simple  wounds  of 
the  skin. — Denudation  of  the  dermis. — Mucous  and 
cartilaginous  transformations. — Cancer.  271 

III.  Alterations  in  the  Development. 

Defects  of  conformation. — Preternatural  cutaneous  tex- 
ture (cicatrix). — Various  kinds  of  cicatrices. — Mecha- 
nism of  cicatrization. — Characters  of  the  new  cutane- 
ous texture.  275 


ADDITIONS  TO  THE  EPIDERMOID  SYSTEM. 

Means  of  Union  of  the  Epidermis  with  the  Dermis. — Exhalant 
and  Absorbent  Fores. — Nature  of  the  elongations  inter- 
mediate between  the  dermis  and  the  epidermis.— 
Doubts  upon  the  existence  of  the  pores.  281 

Epidermis  of  the  Mucous  Membranes. — It  is  not  known 
whether  the  deep-seated  mucous  membranes  have  an 
epidermis. — Line  of  demarcation  apparent  in  some 
places  between  the  superficial  and  the  deep-seated 
mucous  membranes.  284 

Mature  of  the  Mails. — They  are  a dependance  of  the  horny 
layer. — Analogous  parts  in  animals. — Mode  of  forma- 
tion of  the  nails  and  the  horns. — Longitudinal  stri$  of 
the  nails.  . 286 


328 


ANALYTICAL  TABLE  OF  CONTENTS. 


MORBID  ANATOMY  OF  THE  EPIDERMOID 
SYSTEM. 

PAGE 

Various  Alterations  of  the  Epidermis. — Its  destruction. — 
Excrescences  of  the  nails. — Other  alierations  of  the 
nails. — Nail  entering  the  flesh.  288 


ADDITIONS  TO  THE  PILOUS  SYSTEM. 

Structure  of  the  Hairs. — Arrangement  of  their  bulb. — Or- 
ganization.— Body  of  the  hair. — Two  opinions  upon  its 
structure. Colouring  matter  of  the  hair. Conse- 
quences. 291 


MORBID  ANATOMY  OF  THE  PILOUS  SYSTEM. 

Whiteness. — Alopecia. — Nature  of  the  Plica. — Preter- 
natural hairs.  295 


PRETERNATURAL  TEXTURES. 


Their  description  belongs  to  general  anatomy. — Common 
characters. — General  arrangement. — Mode  of  produc- 
tion.— Differences.  299 

I.  Of  Tubercles. — They  have  two  periods. — 1st  Period; 
miliary  or  crude  tubercles. — Cyst  of  the  tubercles. — 

2d  Period  ; softening. — Various  termiiiation.s.  303 

II.  Of  Scirrhus. Its  anatomical  characters. — Its  varie- 
ties. 304 

III.  Of  Cancer. Synonyms. Characters. Period  of 

softening.  305 

IV.  Of  Melanosis. — It  dififers  from  the  black  matter  of  the 

lungs. — Its  distinctive  characters. — Its  nature.  306 


THE  END. 


I 


